Weak knowledge of audio and video: March 2011

Sunday, March 27, 2011

【 Weak current College 】 room decoration ([third] audio enthusiasts decorated four elements)---Power By 【 China power house network 】

Some people buy imported audio equipment, although the giant, but at a cost of sound effect was not good, and "tupao family enthusiasts get cheap equipment being also compared. After several well road "authority" to hear the consultation, it is the listening environment is poor. Improve listening environments, is to improve the quality of audio playback

1. Select the best room and the best location for home theater and music room its best shape of a rectangle to a bigger room area are ideal as possible, but due to the limited room conditions, you may receive multiple undesirable room shape and size, you should note that in the main room speakers placed left and right sides as symmetric. Square room, can also be taken to the main speakers to the corner store for the Center. Audio device and audio visual location should be in the room longer ends, two main speaker distance shall be not less than 2 m and with audio-visual location into the isosceles triangle or an equilateral triangle, the primary speaker positive should be slightly to the inside to the splay, lateral and back away from the wall of the best stay 0.3 meters of space. Its height generally eschew slightly higher than the person sitting at the height of the ears.
2. to reasonable selection can in acoustical materials House decoration, consider some of the features of a certain sound absorbing material is the best, such as non-woven wallpaper, wallpaper with Emboss patterns. But also it is necessary to pay attention to avoid paving acoustical materials, this will make the sound, hair-dryer, astringent, lack of mellow sweet sense of space, also losing the charm of music. If the room condition is limited, it is not possible to do alone opening a home theatre or room, then place the sound in the living room and do in home theatre or listening environment is selected, if the study or the bedroom as a home theater or listening environment, the effect may be larger. If one side is the cement walls, while the other side is a large cabinet furniture, in the cement wall side suspension or two pieces of cloth with absorption of decorative painting or tapestry, to do some acoustic treatment of compensation, so that the main speaker of both sides of the acoustic performance as close as possible. If figure simple easy to use floor curtains, carpet can receive a certain amount of sound-absorbing effect. This can be effective in reducing some reflections, enhance audio clarity, thus improving listening.

3. to securing doors and Windows, soundproof anti-vibration enthusiasts generally has this experience, that is, when the music up, a part such as doors and Windows or other small items as the music that is a section of frequency hum along. This kind of resonance phenomena in order to avoid effectively, you should be aware of the indoor ceiling is made of cavity type, furniture or better, with less and should avoid exposure of cabinets and furniture placement, because it is in fact cavity; audio environments are advised not to put light shell craft jewelry. Glass doors and Windows (including the furniture door glass), be sure to install the firm, and note pad at the gap. If the listening environment away from the noise of the city, and near excessive noise measures should be taken, in addition to seal gaps, best Windows and doors can be changed to double glazing so noise performance greatly improved. For vibration reduction to a minimum, may wish to use the "I" shape or "Z"-shaped speaker rack up the speakers, unconditionally, or speaker at low Cabinet, but the best low Cabinet, inside need steady full articles.

4. to use the power line in meter to swap for more than 5 amp. Sound electricity, kitchen use electricity, lighting, air conditioning, electricity, etc. also have their own established dedicated to influence each other. If the condition is limited, at least you should separate the audio equipment to host a special line, and the best and other home appliances to avoid while you use the vacuum cleaner, hair dryer, microwaves, computers, air conditioning, electrical power is generated, the resulting clutter noise and Visual effects.

【 Weak current College 】 Ballroom stage lighting and light difference---Power By 【 China power house network 】

People usually are not normally pay attention to lighting, stage lighting and ballroom. In fact, there are still differences between them is not so hard, especially with the TV Studio, entertainment, its boundaries are no longer so evident.
Speaking of the difference between the two, the following aspects are important:
First, use the occasion General in theatre, performing arts center, to shows, conferences, and so on, then we are configuring a large number of stage lighting, and to slow rocking bar, dance halls, entertainment-oriented, you should configure Ballroom lamps.
Second, the lighting in the performing arts, such as the Theatre Conference, often in light to light on the face, ears, side light, light, sky light, etc., to meet the needs of the theatre stage in ballroom, etc, we give greater consideration to light colors, patterns, transformation, and compare free light distribution.
Three types of stage lighting, lamps used in General is a regular fixture, for example: the back lights, spotlights, soft light lamp, astigmatism lights, etc., and ballroom lamps is generally: Magic Ball, pattern lamp, lights and other conventional lamps, in recent years, luxury establishment is dominated by computer lamps, such as scanning lamp, head light, laser light, etc.
Four types of stage lighting, light the light source, typically reflective pickled, quartz bulb, bulb, trichromatic lamps, ballroom lamps General to halogen lamp, gas discharge lamps, etc. 5. control mode arena fixture at dimming, control of Silicon case, mainly switching, dimming, color, etc., ballroom lamp greater use of switch plate or computer console control, mainly on color running programs, pattern change control.
Of course, as the computer lamp technologies and development, and theatrical diversity is also a large number of lamps, computers, using the scale, the regulation on and dance hall lights still not the same.

【 Weak current College 】 let your home audio sound more pretty!---Power By 【 China power house network 】

Rule 1 half-yearly comprehensive clean contacts once

We all know, the metal is exposed to the air near the surface will have the phenomenon of oxidation, losing luster, become darker. Even if the signal line plug gold plated surface after processing, is oxidized, and fuselage plugs and in close contact, but as time went by, there will still be a certain degree of oxidation causes bad, so most every half a year is going to clean it again. Just use the cotton with alcohol smudge contact will be able to do the heavy work, you can make the best contact, contact reply voice is clear and transparent.

Rule 2 cleaning the CD laser changtou

Apparently there is only one laser changtou smaller area, but rely on it to read the CD disc the mark on, so on as long as the adhesion on changtou minimal dust that can affect the accuracy of the reading the signal. Although most of the CD player has the seal of the fuselage, but don't forget to often a disc into the disc there are gaps in the dust, boxing, for a period of time, the surface will leave changtou or less dust, then they will have to tighten the screw-on cover, open the cover direct use cotton swabs on alcohol cleaning. Although there are a variety of available cleaning CD discs, but you spent selling, the so-called wash CD discs can only rely on a line of credit to sweep away the dust or is the use of such by turning to the flock and dust, the effect is not comparable with the direct use cotton swabs thorough. When you're that old CD is not a wash machine clean finished, then listen to when you have opened a layer of yarn and the feeling of old high-frequency response, and also high-sounding details clearly. The cleaning steps changtou probably doing it once a year, even if it is to use the Pioneer of reverse-sing-up system (laser head down rather than up), the dust would still be the electrostatic changtou attract and adhesion, so this work is still not province.

Rule 3, as far as possible, avoid machine folding machine

Based on environmental issues and to equipment placed original stack like impotence, to have the conditions, you should try to be the most important news sources and PA CD part independent to ease, because overlapping display cause harmonic oscillations and the impact on the machine. When the Horn playing music, the vibration of air so that the equipment following the earthquake, two machines will be overlapped each other missionary harmonic oscillations to the music of nebulous micro message, and the band transmission interference, resulting in the sound of pollution, and if one is a CD player, when the motor itself play discs even go further exacerbated the harmonic effects of earthquake magnitude, is even greater. So you want to put the equipment independently on the solid housing.

Rule 4 fission power supply and host, Mono distance between rear-

Today even a lot of price fore has a box the size of separate power supply, Aberdeen, simply fire cattle and host separated into two parts, the benefits of nature is to machine parts and AC adapters may cause interference. If the separate power supply for placement next to the fore, that's a bit meaningless, get away from it, such as the former level in another layer of rack, real-time can hear the overall increase in the degree of insulation, some audio and video will be accurate. Mono-after the level, conditions of two pieces of equipment from point located, guarantee favourable harmless.

Rule 5 repeal CD machine output with adjustable volume

Many single CD player are equipped with adjustable volume output, so you can use the remote control to control the volume, if you don't have this adjustable output is big you can make it fail, even the headphone output on the front of the fuselage, in no case can also be repealed. These two sets of signal output is divided by the main signal, abolished, it only takes a set of fixed volume output will not have thinned the signal output of energy, may become more real sense on the net, force better than before. To repeal these two sets of output methods is not complicated, just open the cover, out within the connector.

Rule 6 interference less sound more pretty

Interior of household electrical appliances and computers should avoid reproducing share a set of power, even if you want to put together should also draws its power from elsewhere. Secondly let wiring together will make the line and the line between the absorbed noise damage sound quality. Regardless of the equipment or connectors, should maintain from other electrical equipment or power cord.

Rule 7 speaker set-up

The Horn of a substantial audio use as an integral part, well it will be too late for playback. How to find the best room in the placement of a person who, in addition to exams has listened carefully to the effects of different placement, you can call the relevant experts for guidance.

Rule 8 Dim environment conducive to listen to the effect
　
Turning off the lights to listening to music is a matter of habit, and playback unrelated, just in the dark environment, particularly sensitive ears, and reduced vision impairments on the audio screen and the position of the recombinant and musical instruments will be feeling a sense of clarity, the atmosphere of better and more open light compared to captain, you can also use other more Dim lights to create a listening environment.

Rule 9-absorbing

In General, furniture within a family environment is already a good odds of sound-absorbing materials, not to sound too cumbersome, Lynette shop a rug is already a basic increase absorptive effect. Plus the benefits of the carpet is reduced floor reflections, avoid mixing positive voices cause turbidity, want to know your room if you need plus the carpet, tiles on the floor of the change in the test sound will know. Speaker distance too close to the back wall, or you can consider when adding a site to increase the sound-absorbing effect tapestry, but pay attention to the unavailable too large, otherwise you may even UHF also smell. In addition, the room of the glass and mirror will have a strong reflection sound effects that need to use curtains to Eclipse to solve the problem. Require high friends more might in the corner and indoor sound reflection points do more acoustic, but pay attention to the sound is not too much, just the right amount of reflected sound help sounds crazy and lively.

【 Weak current College 】 how computer lamp work?

DMX512 is the lighting in the work of a high-frequency words, and how computer lamp? computer lamp control and how to do?
Intelligent lights typically use DMX512 control protocol control lights of various actions. This control protocol called 512 Protocol in the industry. It is a dedicated full digital signal control protocol, compared with analog signal, it has a signal more stable, flexible and convenient way to control, and is not vulnerable to environmental interference, etc. Therefore, DMX512 signal is by far the most popular control signal. DMX signal can control all 512 channels.
Typically, an intelligent lights on the occupation of a channel operation. If the computer lamp, a color wheel to change the color on the occupation of a channel, if computer lamp with two color wheel to change the color on the occupation of two channels. Computer lamp function, the more it occupied by a channel number. Generally speaking, the number of channels determine the computer lamp performance. Features of PC lamp only 4 or 8 channel but powerful PC lamp can have as many as 38 channel. This high-performance computer lamp, an action can consume 2 or more channels. For example, high-performance computer lamp horizontal movement is divided into fast horizontal movement and accurate horizontal movement; a computer lamp strobe is divided into a stroboscopic, random strobe, slow light fast charge light strobe light, fast and slow your light strobe and so on many kinds of effects, strobe will occupy more than one channel.
Because all the DMX signal can only control 512 channel, therefore, in the design of computerized light control system must take into account a DMX control line behind all computer lamp channel number and cannot be greater than 512 channels. Otherwise, it must increase the DMX signal input number to resolve. Each additional way DMX signal, it is necessary to increase the signal line all the way to independence.

College】【weak role of movements and calculation of the stage.

1. . Lifting platform is outlined in the audience stage machinery equipment one of the most widely used equipment in the professional opera, dance theater, Theatre, are equipped with a large number of various types of lift, even in some of the turntable .based Theatre, rotary drum are also equipped with different specifications of the elevator or lift blocks. .Many international well-known music hall, all equipped for the band, choir or large musical instrument of the lift. .Some experimental theater, the stage in order to achieve change in the form in the whole audience full of modular design by lift. .The National Grand Theater, for example, the Opera House audience devices, there is forty five lifts, turntable drum drama within the field, set the two lifts and thirteen lift the block, a concert hall audience with three .block lifts and a piano lift. .An experimental theater design, the arrangement of twenty four lifts. . 1.1 The role of elevator lift role in the theater as follows: 1.1.1 quickly moved to set the stage for the main performance area layout of the main lift is mainly used for fast moving .theme. .Typical of "goods"-shaped arrangement of the song, dance theater stage, the lift station and back and side-car turntable with the entire board, or part of the scene fast conversion. .This arrangement allows three full sets of rapid conversion. . 1.1.2 meet the needs of process layout of the stage of "goods"-shaped arrangement of the song, dance theater stage, in the main stage lift the front, back, left and right often arranged auxiliary lifts, side, .After the secondary lift stations and for the side of the car after the car out of the smooth turntable, the former auxiliary elevator car turntable is used to place closest to the station after the position of the mouth. .In the side of the car after the vehicle turntable platform and complement levels following lifts, can be in the side of the car after the car platform or turntable fill out after the table level, so that the whole table height does not appear to guarantee the safety of performers and staff. . 1.1.3 Stage Design and repertoire director to meet the needs of staff in different repertoire , in accordance with requirements of stage design and directing staff, can use a different lift height to change the shape of the stage, to adapt the story of the set .or venue requirements, take the scene to save consumption of manpower, material resources. .Use of the tilt device lifts the formation of tilt table, a better performance in all kinds of emergent perspective effects. . 1.1.4 according to the needs of the story to create a special atmosphere and the effect of stage machinery own date appears even the simplest of stage machinery, and are often involved in performances, according to the needs of the story, to create a number of .atmosphere and the effects of the accident. .For example, the use of low-speed lift the boat down the performance of the sea, the use of the valve lift and actors on stage performance of personnel lifts, and appeared so suddenly disappeared. . 1.1.5 performing schools according to different needs, changes in the form of stage example, using the orchestra pit lift and can be the big theatrical-style sets the stage lip out together even in experimental theater ., the use of lifts can do theater ended with the stage, out-style stage, island-style stage, intermediate-type stage, T-shaped stage or in the hall and other forms. . 1.1.6 as a storage lifts performed by Taiwanese blankets, tools and other soft landscape pieces some theaters in the appropriate place on the stage with soft landscape library established for Taiwan lifts blanket, soft landscape pieces .storage. . 1.1.7 using the vertical lifting platform as a tool to transport a lot of theater's main stage rear end or side of the stage, with scenery container transport lift for vertically transporting the goods from the ground .stage in a specified location or plane. .Orchestra pit lifts are often used to transport activity seats. . 1.2 lift arrangement and size of the box theatrical run, the arrangement of the main stage elevator areas often coincide with the theatrical performances of different genres require different sized performing area, usually the main stage lift .To cover the performance area and the prospect area. .Process layout according to the requirements of the stage, the stage and set with side table and side of the car, set the corresponding position in the corresponding auxiliary lift and fill level lifts, a car after the turntable and set the stage when set in the appropriate location as needed before .adjuvant lift and fill level lift. . .

【School】 Chunlan weak video conferencing program analysis --- Power By 【China】 weak home network.

a background overview of Chunlan (Group) Corporation is a manufacturing, research, investment, trade in one of the diversified, high technology, international large modern companies, is the largest 50 business groups .. .Chunlan headquarters under the jurisdiction of 42 independent subsidiaries, including 18 manufacturing companies, and has Chunlan Research Institute, Chunlan College, Chunlan post-doctoral workstations and Chunlan Electric Institute, Chunlan Motor Research Institute, Chunlan electronic and other research, educational institutions .. . Changing due to market information, the group need to respond quickly, it may fully grasp the market. .Rapid feedback on market information to decision-making, enhance service quality, reduce operating costs, the Group decided to introduce high-level video conferencing system. . Second, the user needs the face of numerous subsidiaries and distribution outlets to participate in relevant meetings of personnel becoming Chunlan need to face a large expenditure, and because of the large number of .scattered throughout the country, the meeting place of choice to coordinate arrangements for the parties to work to become a cumbersome and time-consuming entry thing, in this case, the Chunlan Group decided to build a video conferencing system. .The construction of the video conferencing system should be able to meet the various regions to the meeting venue at the same time, and can two-way audio and video communication. .The participants do not need two-way video, should be able to make it through one-way PC-to watch and listen to the live conference. .For the main venue, should be able to meet the leadership of the main venue of the conference also attended the meeting to watch the picture of the situation and can any one venue on the remote control camera. . Third, the application features 1, the meeting can be a variety of modes: the above video conferencing system design is completed, can be used for the following meetings: ▲ support the President complete control .pattern of meetings, in which the meeting mode, viewing the object of the conference venue completely specified by the center, leading the freedom to choose and select any venue poll to watch, together with the remote camera control functions DSTH.323MCS President venue for any .control of the venue of the camera view to adjust to the appropriate location and compare this model applies to President speech patterns. . ▲ also supports voice-incentive model, the model without administrator management, application and free discussion of the meeting. . ▲ mix by DSTH.323MCS, mute, Mute function, and "conspired meeting" to discuss a few venues can be individually and not by other unrelated to the venue to hear, and without interrupting the meeting. . ▲ meeting in the President's speech patterns in order to fully ensure order at meetings, the general venue is not free speech, such as the special circumstances need to speak, can speak through the hand-held remote control application for approval by the leadership, the party can speak .. . 2, remote camera control application: In the meeting which, generally have their own arrangements for each camera position the venue to venue transmit the image itself to other venues to watch, but this approach often fails .The main venue to meet the goals you want to adjust the viewing needs. .For example, when a speech at the venue, the other venue is sometimes necessary to view the panorama hall, sometimes watch a spokesman, a spokesman for the venue if the statement continues to change, but also need to change the view objects. .In this case, if the primary site can not be according to their own desire to adjust the camera shooting the object of the venue, the meeting of the effect would be unimaginable. . According to this demand, DSTMedia supported cameras as the industry's first remote control (FECC) function of MCU manufacturers, making it MCU multipoint conference held in the remote camera can be easily controlled, and in cascade .Among the meeting, this feature can also ensure a smooth implementation. .In this way, but the main venue of the speech venue to watch anywhere and people can easily be adjusted. . 3, the terminal application requests to speak: in Chunlan video conferencing and remote training, often have the following scenario: when the President or the speech of teaching personnel, other participants are sometimes .requests to speak, but to ensure that the meeting order at meetings, often speaking in advance of the conference will not be a mute, so that the venue will not be able to speak to say a word. .To resolve this conflict, DSTMedia MCU support R & D is muted in the case of the terminal by remote control for the floor, so that both the order and ensure the meeting expressed their requests to speak. . 4, TV wall server applications: video conferencing system in Chunlan, we applied the multi-screen video wall server, can well meet the high-end users for high-definition video conferencing, multi-screen applications .the venue will be 46 by 46 television screens to display simultaneously. .TV wall server is a separate hardware device, used in the center of the video conference system main venue, directly connected by cable 100M MCU, the panel on a single server with 8 composite video output terminal, built-in decoder 16 to achieve two .block independent display card output. .Video cable can be connected directly to the different display devices. .Each TV can display at the venue or a separate split-screen mode to display more than one venue, the video resolution is 4CIF, frame rate 25-30fps. . 5, the user group management application: Chunlan Group video conference system for all users to group management, which is an advanced design concepts, greatly facilitate the users. .The specific advantages are as follows: ▲ user group management is simple and intuitive, users can quickly find the user group, and its operation; ▲ Conference when the user changes the case of regular, group management can .greatly reduce the complexity of the user's operation, the number of users, the more you can show the advantages of grouping; ▲ When the user needs initiated through a terminal session, use the grouping feature will greatly reduce the burden of meeting organizers, it is conceivable .If there is no user group, the user terminal in the use of the launch meeting, the need to individually enter the name of the venue, if the venue is large, the organization who is a considerable burden, and use the group, regardless of the number of users, organizations who are only .need to enter a group name to complete the call to all terminals, is very convenient. . 6, multicast applications: multicast service is based on the IP network protocol under the application of one of the most basic way, it can be said to be inherent in an IP network a very useful advantage. .As the meeting room capacity is limited, the number of people attended the meeting to be limited. .But many meetings always want more and more people understand the spirit of the instructions to the conference. .For this problem, the MCU DSTMedia has multicast capabilities to live in real time the meeting is sent to stream media to the network. .Customers only need to use the PC, and use the appropriate receiver can receive the live broadcast of the meeting, but not limited the number of people watching. . Four runs feedback Chunlan Group is the video conference "to eat crabs", back in 2001 to enable this system. .Because this program to build in technology, application models are highly representative repeatedly been rated as excellent third party solutions, but also by numerous corporate video conferencing systems as building a model. . Using this system, Chunlan's senior management and marketing staff all over the frequent communication between the can and exchanges, timely and accurate transmission of sales policy and market information, thus greatly improving the speed of market response and sales supervision. .In addition, the Chunlan meeting in the use of the system, it is also the system for overseas employees with remote training, technology and marketing strategy discussions and other activities, the indirect economic benefits are far greater than the direct savings in the cost of traditional contributions. .According to the data revealed Chunlan Group, the introduction of a corporate video conferencing systems management, the year will save about 30 million yuan fee, which greatly reduces the cost of business operations. . .

Weak current College】【easily buy projector of parameters analysis --- Power By】【China power house network.

Projector's parameters, which give many people choose to set a certain threshold, the purchase of technology needs to take the time to understand. But in fact, the projector is like other electronic products, as long as you understand some basic indicators, to buy is no longer difficult. Today we will have some of the main parameters of projector to everyone, convenient charging before the purchase.

Resolution

Is the resolution of the projector and the connected computer. To enable the selected projector rendering the most perfect results, recommendations will be transferred to the computer and the projector's resolution.

Brightness

Brightness projector key performance indicators that are directly related to the Viewer is clearly recognizable graphic text on the screen. In General, for dozens of small and medium-sized conference room, room size to 100 inches to 120 inches (2.13 m-2.44 m) wide screen, there are 2----2500ISO lumens around enough. However, you also need to consider its mobility. In the light particularly sunlight strong environment, projector brightness to the appropriate increase.

Weight

By weight as a standard, the projector is divided into three categories:

1. the portable projector

This is often used to carry out customer design. It is characterized by small size, light weight, generally within the volume size 2kg allowed to carry on the aircraft. As a result of such users are using laptops, XGA resolution is standard, and this type of projector user to minimize the volume, weight, so in brightness and other performance has been sacrificed.

2. desktop projectors

This type of projector volume slightly larger cargo can be permanently installed on the floor or cope with a small amount of mobile use. This type of projector brightness than portable projector to high, the fellow projection image quality also has a large and moderate prices. This projector has flexibility and good price/performance, general business and educational use.

3. fixed-mounted projector

This is a large Conference Center, command centers, large-scale ladder classroom design, installation in place generally no longer move. This type of projector in brightness and image quality is the highest level, and to adapt to different installation and usage, there are many optional options, such as lens, signal processing Board, etc. But the installation must be completed by a professional staff, the maintenance of the more complex, the price is very expensive.

Contrast

Contrast is the projection of the projector screen to the brightest-darkest areas of contrast on the Visual effects of second only to the brightness target, generally the larger the contrast ratio, the image clearer.

Uniformity

Any projector shoot out of the screen there will be a central area and the four corners of the brightness of different phenomena. Uniformity is reflected edge brightness-luminance ratio of Centre, the higher the screen uniformity of uniform consistency, the better.

Lamp life

LCD, DLP projector has an external light sources, their life is directly related to the cost of using the projector, so at the time of purchase must ask the lamp life and replacement costs. Projector lamp life is 2000 hours, replacement cost about $ 1 $/hour.

【 Weak current College 】 list of global famous audio amplifier

North America:
Bryston (thanks to the thing passes), Canada's most representative products of transistor amplifier, long life, sound rational, strength of the foot
SonicFrontiers Canada Hi-End Danji, timbre and delicate noble, strength of the abundant
ClasseAudio (driving potential) Canada famous transistor amplifier, delicate timbre, musical enrichment
SimAudio Canada famous Hi-End transistor amplifiers, advanced technology, outstanding sound quality
Anthem version of cheap Canada SonicFrontiers, producing high quality danji, sound pretty price adjustment
AudioResearch United States top Hi-End Danji representative brand to danji, sound, taste, speed
MarkLevinson United States top Hi-End transistor amplifier model level, representatives of neutral tone
In the price of ProceedMarkLevinson Hi-End transistor amplifiers, focus on AV products
CelloMarkLevinson created top Hi-End transistor amplifier of high value, quality unmatched
Krell (Kellett) United States top Hi-End transistor amplifiers, thrust, musical spectacular
McIntosh (wheat warehouse photo) United States classic Hi-End bile/stone amplifier, sound noble, collection value
Cary (Galilee) in the United States in recent years, the high danji producers to enter the digital realm
ConardJohnson (poem drunk) United States, the representatives of classical danji timbre noble fengrun
Dynaco United States representative classical, in Valence Danji timbre very rich sense
Passlab (Perth) United States heavyweight Hi-End transistor amplifiers, sound noble smooth
JeffRowland (Lok Lam) United States well-known Hi-End transistor amplifier, power relationships with music very persistent
Parasound United States representatives in the low price, has a transistor amplifier "poor," says Krell
Sunfire United States famous price advanced biliary/stone amplifier, strength of the sinking, musical excellence
Threshold United States well-known Hi-End transistor amplifiers, technology application in advance
VAC United States veteran Hi-End Danji, more to split design, quality as army equipment
VTL United States veteran advanced danji, stable quality, large thrust
C.a.t United States model the least advanced danji to a SL-1 bile fore established Hi-End level status
Canary (Canary) United States emerging Hi-End Danji, exquisite appearance, voice and delicate noble
B.a.t United States emerging Hi-End bile/stone amplifier, design and sound principles of the "balance"
Hovland (Hao Lung) United States emerging Hi-End Danji, sophisticated materials, look gorgeous
Herron United States emerging Hi-End bile/frugal appearance of stone amplifier, internal strict, sound clearly open Jan
B & K United States well-known high transistor amplifier in price, the price is high, the Stereophie "bangzhong flyers
Manley United States well-known Hi-End Danji, design sophisticated level, sound clear and moving
Aragon United States well-known Hi-End transistor amplifier in Valence, in recent years with regard to audio and video into the
Ayre (yiya) United States well-known Hi-End transistor amplifiers, exquisite materials, tones and natural comfort
The European region
Gryphon (GUI Feng) Denmark heavyweight Hi-End transistor amplifiers, sound noble strength
Primare (翩 beauty) Denmark boutique-Hi-End transistor amplifier, timbre and delicate smooth noble
LA.Audio Denmark Danji in price excellent, detailed and vivid colours with a sense of nobility
Bow (Denmark bow) Denmark famous advanced transistor amplifier, distinctive and external production
TactAudio Denmark emerging Hi-End digital amplifier, the workmanship excellent, tones and natural comfort
Densen (Denmark Prince) Denmark boutique level price Hi-End transistor amplifier, music round pure
CHORD (chord) of the United Kingdom, the famous listening level Hi-End transistor amplifiers, workmanship and excellent sound quality
Matisse (Matisse) United Kingdom famous Hi-End Danji, timbre and noble, meticulous
MusicalFidelity (music fax) United Kingdom famous advanced transistor amplifier, sound and smooth natural, instinctive feel strong
Exposure (Lippo) United Kingdom price of Guinness in transistor amplifier spokesman, meaning, strength is more important than appearance
Rotel (Yao) United Kingdom price transistor amplifier in the famous, cost-effective
United Kingdom Danji new advanced EAR, is said to be B & W, ATC, Thiel perfect sound
AudioNote United Kingdom famous Hi-End Danji, many design for low power single-ended, for the sake of bronze acoustic material at a high
Audion United Kingdom famous high price, sound sense strong danji, excellent timbre
Venture (MK) created by Chinese Belgium Hi-End brand, products to speaker, danji supplement
AudioAnalogue (Gagaku) Italy emerging high transistor amplifier in price, sound great literary atmosphere
UnisonRexearch (phonology) Italy famous Hi-End Danji, elegant, charming sound quality
SPHINX (Ling Lions) Netherlands famousHigh-priced Hi-End transistor amplifier, sound fresh and neutral
NAD (Le Ting) United Kingdom famous price transistor amplifier, high performance-cost ratio
Arcam (Ya chun) United Kingdom Cambridge area price transistor amplifier, timbre and meticulous, and value for money
Quad (countries) of the United Kingdom, it is the classical senior danji beautiful music of representative
LINN (Lotus) United Kingdom Hi-End diversified manufacturer that is famous for its transistor amplifier small, timbre and moving
AMC United Kingdom parity bile/stone amplifier, stable quality, strong sense of
Rega (gentleman) in the United Kingdom, cheap transistor amplifier tone-exquisite and elegant
TAGMclaren (Jimmy get LUN) United Kingdom emerging in high transistor amplifier, well-made, tone permeability rich sense
Onix (Europe Dennis) United Kingdom price transistor amplifiers, neutral tones and simple
CambridgeAudio (Cambridge) United Kingdom Cambridge cheap transistor amplifiers, cost-effective
Manley in United Kingdom emerging low-priced transistor amplifier, look chic and beautiful, good sound quality
Creek (long) United Kingdom established in low transistor amplifier, simplicity, quality and beautiful appearance
Electrocompaniet (musical journey), Norway's most representative Hi-End transistor amplifier, elegant permeability lifelike music
Asia-Pacific region
Plinius New Zealand Hi-End transistor amplifier, the use of materials, prices, plain
MAS Australia Hi-End transistor amplifier, production materials and solid, big potential
MelodySHW (mailedi) Chinese created Australia emerging advanced danji, distinctive timbre, musical rich and colorful
HALCRO Australia emerging powerhouse-Hi-End transistor amplifiers, lowest distortion history
Denon (Tianlong) Japan has a long history of advanced transistor amplifier, specializes in audio and video products
Onkyo (Onkyo) Japan brand transistor amplifier, audio amplifier-
AIR-Tigtht Japan Hi-End Danji, much to focus on one small power line
Accuphase (voice) Japan famous Hi-End transistor amplifier to produce precise fine
Marantz (malanshi) is the United States Japan Consortium for control of the brand price bile/soft rock amplifiers, tones, rich sense
SONY (Sony) Japan famous diversified audiovisual producers, he focuses on audio and video products
Luxman (Guinness) Japan established high bile/stones, sounds soft, plump amplifier
AudioSpace Hong Kong senior famous danji, the workmanship of sophisticated, cost-effective
Proton (proton) Taiwan famous transistor amplifier one of pioneer, voice control and price comparison
Bada (Bada) China Hi-Fi transistor amplifier one of pioneer, voice control and price comparison
Opera (obur) one of the representatives of China Danji Hi-Fi, appearance and meticulous, sophisticated materials, high cost performance
Spark (Gernsback) one of the representatives of China Danji, Hi-Fi sound quality with production premium
Korsun (Caldwell song), one of the representatives of China transistor amplifier, sound neutral alcohol is
Xindak (Dirk) famous stone of bile/Hi-Fi amplifier equipped with material, sound quality and high cost performance
Winner (Tin Yat) famous hi-fi transistor amplifier, thick warm tone at affordable
ShengYa (acoustic ya) China veteran Hi-Fi amplifier bile/stone, solid and appearance-grade power,
Bell voice of God/the Phoenix Chinese famous Hi-Fi transistor amplifiers, advanced materials, sound better
Denmark wafer (vifa)

【 Weak current College 】 professional audio terminology in English (3)---Power By 【 China power house network 】

Ccathode anode cathode,
CCell battery
CCenter Center
CClear clear
CCold cold (-)
CAcable cable
Cable cables
Cabinet small control console
CACcoherentacousticcoding coherent acoustic coding
Cache buffer memory
Calcalando decrease volume
CALCalendar class
CALCaliber diameter
CALCalibrate standardization
CALContinuityacceptlimit continuity accepted limit
Calibrate calibration, calibration
Call back, back, breathe out
Can monitor headphones with cartridge
CANCLcancel delete
CANCLCancelling elimination
Cancel cancel
Cannon card Lennon interface
Canon rules
Cap capacitors
CapacitanceMic capacitor microphone
Capacity power, electric capacity
CARcarrier carrier, bearings, air Chuck
Single-Card program, the Board
Cardioid-type of
CATVcabletelevision cable TV
Crispness crispy sound
Category type, type
Cartridge software card pick-up
Carrkioid heart-shaped microphone
Carrier carrier
Transport Cart
Cartridge memory cartridges, cartridge
Cascade series
Cassette tabbed, cassette
CAVconstantangularvelocity constant angular velocity
Caution alarm
CBRcircuitboardrack circuit board holder
CCcontourcorrection contour correction
CCDchargecoupleddevice charge-coupled device
CDcompactdisc CDs
CDAcurrentdumpingamplifier current amplifier
CD-Ecompactdiscerasable erasbale-CDs
CDGcompact-discplusgraphic with a still image of the CD to sing up
CDconstantdirectionalhorn constant to point to the Horn
CDVcompactdiscwithvideo tight sheath audio-visual recordings
CEceramic ceramics
Clockenable clock start
Cell battery, symbols, units
Cellarclub underground club results
Cello cello
CEMAconsumerelectronicsmanufacturer′sassociation
(United States) consumer electronics manufacturers association
CENELECconnector European standard 21 foot AV connector
Cent sound separation
Centralearth Center ground
CESconsumerelectronicshow
(United States) Consumer Electronics Show
CFcenterfrequency center frequency
Crossfade soft switching
CHchannel channel, channel
Chain transport chain, channel
Chainplay continuous play
Chamber acoustics dense tone, anechoic chamber
CHANchannel channel
Change Exchange
Chapter track
Chaperskip Dance Festival
CHAEcharacter characters, symbols
Characteristiccurve characteristics curve
Charge rechargeable
Charger charger
Chase tracking
Check verification
CHCcharge charging
CH-off channel cut
Choke chorus
Choose Select
Chromatic colour, chromatic
Church church acoustics
CIcutin entry
CICcrossinterleavecode cross interlaced encoding
CIRCcirculate cycle
Circuit circuit
CLcancel cancelled
Classic classical
Clean cleaning
CLRclear zero
Click ticking sound
Clip clipping, limiting, Terminal
CLKclock clock signal
Close off, stop
CLS control room monitor
Cluster sound wave effect
CLVceilinglimitvalue cap value
CMPcompact compression
CMPTcompatibility compatibility
CMRRcommonmoderejectionratio common mode rejection ratio
CNTcount count register
CNTRLcentral Centre, central position output COcarryout
Coarse coarse
Coax coaxial cable
Coaxial digital coaxial interfaces
Code code code
Coefficient coefficient
Coincident multiple signal synchronization
Cold cold, thin
Color coloring effects
COMcomb comb (filtering)
COMBcombination combination tone
COMBIcombination combination, mixed
COMBOcombination, combo
Combining collection, combined with
COMMcommunication reversing, switching device
Command instruction, operation, signal
COMMON public, public land side
Communieationspeed communication speed selection
COMPcomparator comparator
COMPcompensate compensation
Compact compression
Compander compression Extender
Compare compare
Compatibility compatible
Compensate compensation
Complete set of equipment Complex
Copmoser creative, composer
Compressor compressor
COMP-EXP pressure diffuser
Balanced Compromise (frequency)
Computer computer, computer
CONconcentriccable coaxial cable
CONconsole control console
CONcontroller controller
Concentric coaxial, concentric
Concert Hall effect
CondenserMicrophone capacitor microphone
Conetype Cone (speakers)
CONFIG layout, wiring connection
Connect connection contact
CORRcorrect calibration, compensation, offset the
Configuration line layout
Confirmation to confirm
Consent universal socket
Console mixer
Consonant consonants
Constant constants
CONTcontinuous continuous (timbre)
CONTcontrol control, manipulation
Contact contactor
Content content
Continuous, continue Continue
Continuebutton two recording deck continuous playback keys
Contour shape, contour, maintain
Contra-octave
Contrast-contrast
Contribution allocations
Controlled controllable
Controller controller
CONVconventional General
CONVconvert transform
CONVconvertible convertible
Copy copy
Correlationmeter related tables
Coupler coupling
Cover compensation
Coverage effective range
CPclockpulse clock pulse
CPcontrolprogram control program
CPU central processing unit
CRcardreader card reader/writer
CRCcyclicredundancycheck cyclic redundancy check
Create build and create
Crescendo crescendo or fade
Sense of Crispness crisp
CRMcontrolroom control room
CROMcontrolreadonlymemory control read-only memory
Crossfader-gradient filter
Cross-MOD cross modulation
Crossover frequency divider, reversing, cut off
Crosstalk channel crosstalk, crosstalk
Crunch rubs
C/Scycle/second week/sec
CSScontentscramblingsystem content encryption system
CSTcasestyletape cartridge
CTcurrent current
CTMclosetalkingmicrophone near speaking microphone
CUcountingunit count unit
Listen to the selected Cue tip
Cueclock fault clock
Cueing tips, pointed out that
The cursor Cursor indicator
Curve (characteristics) curve
Custom General
CUT-cut, hard switch

Weak current College】【listening, sound identification, analysis of the sound-sound quality and transient analysis.

We listen to the Symphony's ups and downs, we appreciate the North American box office champion movie cast recording of the heart, feel the rock and roll and mysterious splendour, but when you concentrate to experience the excitement of the " .Rumble ", do you notice that your favourite headphones also able to accommodate the number of times this ROAR? sound-sound quality Beautiful music, pleasant voice, everyone likes. What a voice like that color is the sound quality .to win or sound slightly superior? around sound effects on this issue, there are a variety of discussion and debate. There is talk about quality, but also on sound effects, flaunted chip, and worship of the headset. But the "quality" and ."sound" in the words of standard definition and understanding, it is difficult to have uniform standards, mainly depends on each person's own feeling. Therefore, also leads to the endless debate. The author, based on sound and players understand, in conjunction with .our own experience, this makes the following points: The so-called sound is the sound quality, sound quality. Specific description of the sound, including sound, tone, timbre and sequences. If it is difficult to understand, you can .use digital photos to illustrate. If a photo color is very pure, very rich level of detail, light and very accurate, we can say that this picture unit "quality" is very good. We can use image processing software for photo .processing, you can put the color concentration, contrast enhancement, sharpening, or add some artistic effects. So we look photo seems to be more beautiful, but actually have on the original picture. Sound quality, we adjust the equalizer enables high .bass enhancement, plus DFX plug-in, and so on, so that we may sound like more wonderful, in fact, many sound details have been lost. Sometimes we sound or image processing and retouching is essential so that you can better .meet the needs of the individual's appreciation. However we do not have to be improving the sound quality, in short, deal with more plugins, more damage for sound quality. Moreover, now many people compare what playback software sound good. Comparison .is not possible, but how do you want to know more, or just to say that ignorance. We listen to music in general are more or less effective when combined with the plugin, but in fact, at this time we only sound .effects only, not the sound quality. If the removal of sound effects, we actually compare the playback software decoder, if you use the same codec playback software, it is almost impossible to compare the differences. Even if you are using a different codec to .decode MP3, are basically very mature> technology. Although there are differences, but is also very small. To our General player, claiming to be able to tell just fooling themselves. There are or not knowing their own comparison of only audio instead of .sound quality. Quality evaluation is terminology: Sound from broken (split): serious harmonic and intermodulation distortion, "poof" sound, have been cutting flat-topped, distortion is greater than 10 per cent. .Sound stiff: the harmonic and intermodulation distortion, measured by instruments, the apparent distortion 3% -5%. The sound made deep fried: high frequency or in high-frequency too much, there are two kinds of distortion. Sound from Sha: high frequency distortion, intermodulation distortion is transient. Voice rough: distortion, slightly more in high-frequency, transient intermodulation distortion. Sound from Hun: transient, headphone speaker resonance peak, low frequency or .low frequency. Sound generous: frequency bandwidth, low frequency, low frequency, reverberation. Sounds dull hair: high-frequency or in high-frequency is too small, or links to sexually too sharp and deviation from the axis .. Sound thin: high frequency or moderate and distortion in the high-frequency, transient, non-transient intermodulation distortion. Sound has levels: transient, flat frequency response, reverberation. Sound and solid: low .frequency, reverberation, loudness enough. The lack of sound emission: MF, MF transient is not good, too much reverberation. Sound stenosis: frequency characteristic narrow, for example only 150Hz ~ 4000Hz. Metal ( .lead skin sound): a high-frequency individual point outburst, the serious distortion. Sound mellow: frequency characteristics and distortion are good indicators, reverberation, transient. Sound has moisture: high frequency and high frequency, reverb enough .. Sound bright and high frequency and high frequency: enough, relatively flat, reverberation. Sound spiked: high frequency and high frequency. Treble deficiency (float): the lack of medium-frequency, high frequency .and high frequency point to in too sharp. Sound dark: the lack of high-frequency and high frequency. Sound reverberation dry: the lack, the lack of high frequency. The sound made straight (wood .): distortion, outstanding points in the low frequency, reverberation, transient. Sound balance (Concord): frequency characteristics of good, small distortion. ROAR: headphone speaker resonance peak serious prominent, distortion and transient are not good .. The sound is clear: high-frequency and high frequency sound in, distortion, transient. Sound has three-dimensional sense (mono mode): frequency response is flat, reverb, distortion, transient. .Sound and transparent: moderate high frequency and high frequency, low distortion, transient. Sound has presence (telepresence): frequency response, especially in high-frequency, low distortion, transient. Sound fullness: frequency bandwidth, low .frequency, reverberation. Sound muted (pine): low-frequency and low-frequency distortion in right amount, very little. Sounds ambitious (potential), and good: loudness, reverb, and low-frequency and low .frequency. Transient - sound judgment .

Friday, March 18, 2011

【 Weak current college 】 teaches you how to buy headphones---Power By 【 China power house network 】

Headphones type
Headset according to the transducer style category, mainly in the circle of the way, such as electrostatic and magnet. Structural separation approach, half-open and closed. From wear formal you correspond, guaershi and fillet gas.
2. open and closed headphones difference
Open headphones shell is open, the open headphones the sound quality of light, natural, no pressure. Because it is open, the sound leakage, the ambient noise will also be entered.
Half-open headphones refers to the opening of the headset was selective, that is, only for certain frequency opening on other frequency is closed, or in a certain direction is open in the other direction is closed.
Closed headphones shell is sealed to prevent outside noise, sound leakage reduction in professional use in monitoring. Sound in General is very clear, detail-rich, low-frequency response is very good, for most people to wear closed headphones are confined only.
3. What is a high-fidelity earphones?
International Electrotechnical Commission IEC581-10 standard Hi-Fi headphones are the main performance: frequency of not less than the 50Hz to xiangyin 12500Hz; typical frequency response tolerance ± 3dB; frequency response curve slope not exceeding no octaves around within the 250Hz-800Hz 9dB unit in the same octaves bandwidth within the average sound pressure level difference of no more than 2dB, 100Hz-5000Hz range, sound pressure level for 94dB, harmonic distortion of less than 1%, not more than 100dB 3%; headphone frequency response in 2KHz-5KHz decline between allows to improve the transparency and sense of space.
4. What is the frequency response range of headphones?
Frequency response range refers to the headphones to the air out of band width, excellent headphones frequency response width up to 5Hz-40000Hz, ear hearing range only 20Hz-20000Hz. It is worth noting that the definition of the standard width of the frequency response is different, for example to below average output amplitude of 1/2 for standard or less than 1/4 as a standard, this clearly is not the same. General producer is an output is reduced by 1/2 standard width measured frequency response, that is to say to-3dB as standard, as used by the test standards are different, there are some product-10dB to measurement. This fact is equal to the lower than normal 1/16 to standard measurements. Therefore the width of the frequency response is great expansion. Users in the purchase, you should be aware of the different brands of earphone frequency response width may potentially unused test standards.
5. What is impedance headphones?
Headphone impedance is short for its AC impedance, and its size is coil DC impedance in more than 200 Ω to have professional headphones Jack on the match. In a desktop or amplifier, VCD, DVD TV headphone jack output machines, the general use of the high-impedance headphones comparisons. If you use a headset, a low resistance to put down and then plug in the headphones, then a put down, preventing Burnout headphones headset overload or dislocation caused by broken voice coil deformation, impedance headphones generally easier to promote, Walkman, portable, saving machine should select low-impedance headphones, while also noting sensitivity to high, the Walkman, the sensitivity indicator is more important.
6. What is the headset of harmonic distortion?
Harmonic distortion is a distortion, in the headset indicator is marked, the smaller the distortion, the better the sound quality.
7. What is the sensitivity of the headphones?
Popular speakers, headphones sensitivity refers to the same loudness of circumstances, require input power, sensitivity the desired input power. For walkman, and other portable devices, the sensitivity is a very important indicator. Of course, for desktops, this index is relatively less important.
8, wire for headphones sound effects.
Wire rod for headphones sound effects is an indisputable fact. The HI-FI system, different signal lines, speakers will obviously change the sound of the headphones of course is no exception, in recent years abroad introduced several wire to wire transfer HD580 and 600 provides conditions, famous wire such as Sweden and the United States of Clou Kada, etc.
9. in what circumstances to give headset with amplifier?
To the ear with amplifier has the following three conditions, namely the audio sources such as CD/DVD player does not have a dedicated headphone output jack, now you can with a headphone amplifier, CD/DVD player's audio line out (LINEOUT) with two signal lines received power amplifier of audio input jack. In the second case, a low sensitivity, high-impedance headphones, using existing sources such as Walkman it stops, you have to purchase the headphone amplifier. In three cases is high-end headphones, using existing headphone jack in introducing such headset can't play out headphones increase the potential of a headphone amplifier can make sound quality further improved, in this case, we should consider purchasing a high quality headphone amplifier.
10, electron tube headphone amplifier cargo transistor headset amplifier the how to buy?
The current market of tube headphone amplifier using yin-level output for last stage amplifier, this type of circuit structure is very reasonable. Therefore been adopted by most manufacturers. But this circuit output impedance is high, only with 200, 300 and Europe over headphones, and the lower the impedance, the higher the distortion.
Transistor headphone amplifier circuits late-adopting OTL, impedance requirements not strictly, and the lower the impedance, the greater the power output current. Therefore the transistor amplifier of high, medium, low resistance-eat, but to low-impedance headphones to push.
11, headphones sound characteristics
All meals may be better than more familiar to the headset, then we eat. Spicy spicy, fresh flavor, Guangdong, Shanxi people Hi acid. These three taste what you're going to get better? this fear that different people have different view. Features of the headset. European headphones as Bayard, Sen Hai Bessel, AKG, broadly similar, real tone comparisons, clear, clear danrushui. United States headphones as Gaussian, Alice, Goethe,People feel the sound is passionate, humanity and energetic. Japan headset features a CBD aesthetics, beauty of the human voice, sound warm, high-frequency extension of good, sound has been described as being alike LS/35a what music you like, what kind of headphones, you are young or middle-aged people, is what personality, tastes, you decide, from sound characteristics on the above three types only features, there is no distinction between good and bad.

【 Weak current College 】 simultaneous interpretation of Design Guide [illustrated tutorial]---Power By 【 China power house network 】

A simultaneous interpretation of the meaning of simultaneous interpretation simultaneous interpretation, also known as the name suggests, is the basic simultaneous language translation. .Responsible for translation work done by the translator, simultaneous interpretation equipment, the operation interface is provided. .In other words, with simultaneous interpretation equipment, a system composed of these devices can not perform automatic translation of language must be translated by the interpreter. . When people speak different languages to meet or hold an international conference, as both sides or multi-language can not communicate, it must be an interpreter to communicate. .The following language of 1 +2 (that is, a mother-tongue plus two translated languages) example of the process and significance of simultaneous interpretation. .Second, the traditional meeting common is the translation mode A, B on behalf of the talks between the two countries, each with its own, accompanied by translators. .A representative speaking, B country translators to translate their language content, B representatives heard the translation of the contents after the answer, A country translators then translated into national languages of his speech, we put this principle of a simplified process .shown in Figure 1. .<TH Scope=col> </ TH> Figure 1 Another common phenomenon is that A, B on behalf of the talks between the two countries, but only an interpreter responsible for communicating all of the session, we put a simplified schematic process .Figure 2. .<TH Scope=col> </ TH> Figure 2 such a process can clearly see that the whole translation process took at least half the time the talks, and the translator into the core of the talks on the exchange. .Because of this session is face to face, the representatives of the lip, body language are clear, so that relatively more accurate translation, if thetalks more than language, the way this translation is acceptable; but for more than 3 languages .international meetings, this traditional mode of translation can not meet the requirements. .Then you need a set of simultaneous interpretation equipment, each representative wearing a headset receiver and choose to listen to, no matter what language to speak on behalf of all the basic translation of a corresponding member to specify the language of the translation, which .is the role of simultaneous translation equipment. .Three simultaneous modes of modern A, B on behalf of the talks between the two countries, A representative of the country, the interpreter translated into their language A to language B, B to hear the representatives of almost synchronous translated content, and timely .answer, then his speech translator B for the A-language translation. .Similarly, A is almost simultaneous to hear the representatives of the translated content, and timely answer, we put a simplified schematic process shown in Figure 3. .<TH Scope=col> </ TH> Figure 3 such a translation process, you can clearly see the time the talks are timely because the use of electronic systems for voice of interpretation, exchange and distribution, spent .Translation time work only with the reaction speed of the interpreter. . Four simultaneous transmission of simultaneous interpretation system's core technology is multilingual observers signal transmission (distribution, transmission and reception), mainly by the two programs constitute the wired and wireless, and wireless transmission methods are divided into electromagnetic waves .and two infrared methods. . 1. Wired cable transmission of analog and digital transmission is also divided into two ways, through the interpreter from the room, equipment room to each to attend the laying of the location of the multi-core cable transmits multi-channel analog audio or digital audio signals all the way .. .Cable transmission equipment with lower cost, less susceptible to interference, good sound quality, security advantages, but the complexity of the system wiring, routine maintenance is too much trouble, most applications used in fixed installation applications. . Wire analog transmission by the power distribution and load impedance matching constraints, usually audio amplifier transfer constant pressure, so each language requires at least a pair of wire, creating a large and complex wiring systems, electromagnetic interference, .channel crosstalk and attenuation limits the level of the system SNR. .Figure 4 shows a typical analog transmission 1 +3 language simultaneous interpretation system diagram, we can see that, because of the need transfer a total of 4 languages (mother tongue plus 3 Road 1 Road, the language interpretation), so need at least 4 sets of constant pressure amplifier .After the bus transfer to at least 4 seats in the election of each hearing. .<TH Scope=col> </ TH> Figure 4 cable digital transmission can now use the most common UTP network cable, transmission by the digital audio signal sample quantization. .Because digital audio signal using a high bit rate, and the overall sound quality can achieve high fidelity. .And because hand in hand with digital bus connection in a way which simplifies the cabling system, and can make conferencing systems, interpretation systems, voting systems have become a complete portfolio, as shown in Figure 5, the Danish DIS DCS6000 simultaneous interpretation for the wired .A typical system diagram. .<TH Scope=col> </ TH> Figure 5 2. Wireless transmission of electromagnetic waves similar to radio and radio transmit and receive, but generally use lower frequencies and longer wavelengths, in order to avoid .On radio, walkie-talkies and other equipment commonly used bands. .Generally use the wireless electromagnetic transmission antenna cables in the ceiling, floor or walls within the fabric into a closed loop, the receiver receives an induction approach. .Because of this transmission does not have the confidentiality, any person outside the receiver can use the same listen to the conference. .If you use special equipment, or even very far away from the venue can monitor the meeting from the speech. .Wireless transmission of electromagnetic waves Another drawback is that the system susceptible to electromagnetic interference, and even indoor fluorescent light switch will bring the noise, the current field in the simultaneous transmission of voice has been largely eliminated this kind of technology. . 3. Infrared infrared transmission technology due to its simple installation, good sound quality, confidentiality and other advantages, the language commonly used in the simultaneous distribution and transmission areas. .Simultaneous interpretation system using infrared transmission basically consists of the following equipment or subsystems. . Source: pickup microphone, conference system and other audio sources interpretation device: the console, also known as translators, generally have a duplex communications, and digital conference system connected to the control of the host audio, data .exchange. . Audio modulator: Electronic audio signal through the audio cable to the modulator, the modulated infrared transmitter sent. . Infrared transmitter: also known as infrared radiation plate, the electronic audio signal modulated by the RF cable to the transmitter, the use of infrared transmitting tube to cover the entire conference room. . Infrared receiver: in the infrared range, all receivers can receive the infrared receiver is connected to infrared light signals into electrical signals, amplified by the power of multiple channels through a headset for voice monitoring. . Figure 6 shows the infrared simultaneous interpretation for the Danish DIS DCS6000 typical system diagram. .<TH Scope=col> </ TH> Figure 6, the basic functions of five simultaneous analog or digital regardless of technology, a mature, complete with the transmission system should have the following basic features: 1. .automatic switching function site language interpreter when the scene to speak with the same language, change language interpreters do not need to be translated and interpretation device can turn off the microphone for a short break, then interpretation should be able to automatically control the host .The interpretation takes the channel automatically switches to the on-site language. . 2. Second or Relay function interpretation interpretation should be able to receive the device, including native (site language), translated language, multi-media sources and all of the voice, the scene when the translator did not understand language, the system .set automatically translated to another language access for a second or Relay interpreter translated. . 3. Call and technical support functions call each interpretation and Taiwan have independent channels Chairman and technicians, party to an application such as interpreters too fast, technical support and assistance, without disturbing the other participants. . 4. Interpretation channel lock function to prevent the translation of different languages occupy the same channel, the system should be set to channel busy indicator. . 5. Interpretation independent voice monitoring function can control the host language of each channel and on-site monitoring, and with separate volume control. .Six simultaneous interpretation of the design points 1. Source simultaneous interpretation system full access to the central role in the last century is the exchange of a variety of audio, and multimedia signal sources present at the meeting because of the extensive .applications, so the design should take full account of all the voice signal (typical conference system, wireless microphone, etc.), multimedia signal source (a typical computer audio signals, tape recorders, video recorders, CD players, cable TV signal, etc.) .and, most importantly, emergency broadcast simultaneous control of all access to the host. .Because most interpreters have only 1 host 2-way expansion of audio input, so you can design matrix or mixer audio multimedia audio signals to the above pre-entered after simultaneous host. . The most important emergency broadcast signal, because the emergency broadcast system is the trigger time of the accident with the signal output can trigger access to the emergency infrared modulator trigger signal input interface, the modulator can be strong all the output channels .Cut to the set signal source, such as public broadcasting; the current technology is more advanced infrared modulator with independent input for emergency broadcasts, such as the DIS, Denmark's DT 6008 and DT 6032 digital broadband modem comes standard with 2 independent emergency .priority inputs (balanced analog audio format). . 2. Interpreters video source monitoring the relevant provisions in the ISO 2603, suggested the forum, participants, blackboard and projection screen at the same time should be within sight of an interpreter, an interpreter at the meeting conducive to the process .the following can be some of the relevant work. . · Interpreter function can be linked through the camera speaker's lip observed at any time, face and other body language, the translation of the atmosphere more lively and rich; · interpreters can clearly identify the specific location of the speakers, timely .understand the speaker's identity and position of the representatives of the session, a clear part of the special meaning of the language; · interpreter to understand the speakers in a timely blackboard, whiteboard or projection screen to explain the data, drawings, tables or other types of electronic .data, so that the translation is much more accurate. . But in most of the academic hall, banquet hall and other large international meeting applications, regardless of interpretation room setting in any position, this can be compatible with the requirements of various obviously not easy to achieve. .Therefore, the design can take advantage of multimedia video system, the venue of the camera, and computer video signal to the monitor room for all interpreters. . 3. Interpretation of the video source format room meeting room is currently the main video source to composite video (such as cameras, analog booth, video recorders, CD players, etc.) and RGB formats (such as computer signals and digital booth .etc.) based design can be installed in each room video monitor and interpretation of data receivers and 1 units, respectively, access to the system matrix and RGB video matrix. .In order to reduce the use of room space for interpretation, simplified interpretation room cabling system, in particular, to avoid long distance transmission RGB signal attenuation, the proposed design of a multifunctional video frequency processor, the video sent to interpretation room times and RGB signals .frequency processing, and unified format with RGB loop through the twisted pair transceiver receives an interpretation of each room. .Figure 7 with three interpreters room, for example, amount of equipment design and function are described below. .<TH Scope=col> </ TH> Figure 7 · Extron DVS204 1 Taiwan: installed in the control room, responsible for video matrix sent RGB matrix composite video signal and sent to the frequency with component video, select .RGBHV format after switching to a twisted pair transmitter output; · Extron MTP T 15HD 1 Taiwan: installed in the control room, responsible for the RGBHV signals into balanced twisted pair signals, long-distance transport to the interpretation room .Twisted Pair Receiver, 1024 × 768 resolution recommended transmission distance is less than 180 meters; · Extron MTP RL 15HD 2 sets: were installed in the first, second interpretation room, is responsible for the twisted pair signals into .RGBHV signal to the original data in the monitor, because MTP RL 15HD receivers with twisted pair loop output signal, the third room of the twisted pair signal interpretation by the bus loop is also provided; · Extron MTP R .15HD 1 Taiwan: interpretation in the third house installed, responsible for housing the second interpretation of the twisted pair loop sent signals into the original data RGBHV signal to the monitor, and MTP RL 15HD is the difference between the receiver does not have the double .wire loop output. . 4. The number of infrared radiation board design amount of infrared radiation plate installed in the design of the following conditions need to be considered: · the number of language interpreters most of the manufacturers of the radiant panel power .has a different definition of description, but the common feature is a different number of channels in the transmitter that can be derived when the power is different, can be calculated by the following formula: single DIS RA 6013 such as radiant panels in the 4 standard audio .transmission mode coverage of up to 1000m2, but if it is standard for 8-way audio transmission mode can only be achieved when the coverage area of 500m2. . · Venue decoration materials Although not see infrared light, but the acoustic transmission characteristics somewhat similar to: black, rough surfaces than the white, smooth surface will absorb more infrared, infrared emission under such circumstances .Installation of the number should be increased appropriately. .<TH Scope=col> </ TH> <TH scope=col> </ TH> Figure 9 EASE 4.0 covers the results of simulated infrared Therefore, the infrared at different surface decoration materials have different strength and uniformity of power .performance in EASE 4.0 version which already has a simulation feature of these results, but only the built-in infrared board database which part of Germany SENNHEISER model. . 5. Infrared radiation plate installation the infrared radiation the radiation plate has a specific point of view, it is best to have the venue design construction drawings, installed in the building height as possible (such as ceilings or .ceiling), and then simulated infrared radiation panels 1 / 2 power transmission angle, the 1 / 2 power point to cover the largest range (Figure 10). .If building an effective regional presence in a relatively large depression or block, the proposed installation of secondary emission in the region board, cover the blind spot to avoid the infrared (Figure 11). .<TH Scope=col> </ TH> <TH scope=col> </ TH> Figure 10 1 / 2 angle coverage of the simulated power radiation Figure 11 is too low radiant panel installation is easy to transmit signals blocked 6. Design . appropriate carrier frequency RF signals for each channel has its own carrier frequency, concentrated in the vicinity of a certain frequency, this frequency is called the channel carrier frequency, carrier frequency of the highest and lowest value called offset. .The greater the frequency offset range of RF signal, the higher the quality of the audio signal transmitter, capable of firing the less the number of channels. . A. narrow-band modulation narrowband modulation by ± 6KHz ~ ± 7.5KHz FM subcarrier frequency offset method is commonly used multi-channel audio transmission system, the carrier frequency range from 55KHz ~ 1335KHz between each .increasingaccess to 40KHz frequency response range between 50Hz ~ 8KHz, up by 32 standard narrowband transmission channels for transmitting high-definition language. .Relative to the wideband, narrowband modulation frequency response was significantly reduced, but applied to voice transmitter is sufficient because the most important speech is a sufficient number of channels and speech intelligibility. .<TH Scope=col> </ TH> narrow-band modulation is very susceptible to high-frequency switching power supply noise generated by high-frequency noise source types can be divided into two kinds of peak interference and harmonic interference, by interference coupling path .can be divided into two kinds of conduction disturbances and radiated interference. .Main susceptible to high-frequency narrow-band harmonic modulation of radiation interference, interference sources, mostly from the various energy-saving lamps indoors, because the energy-saving lamps in order to reduce flicker, the use of switching power supply to the mains frequency of 50Hz, the frequency rose to 38KHz, it is easy .have 1 or more times 38KHz signal harmonics, these harmonics may just cover the frequency modulation in the narrow-band frequency range, and even 32 channels will have a harmonic disturbance, which affects the SNR of infrared transmission systems .and launch distance. .Number of channels number of channels modulation frequency modulation frequency 055Kz16735Kz195Kz17755Kz2135Kz18815Kz3175Kz19855Kz4215Kz20 895Kz5255Kz21935Kz6295Kz22975Kz7335Kz231015Kz8375Kz241055Kz9415Kz251095Kz10495Kz261135Kz11535Kz271175Kz12575Kz281215Kz13615Kz291255Kz14655Kz301295Kz15695Kz311335Kz Table 1 32-channel narrowband modulation frequency distribution <TH scope=col> </ TH> Figure 13 the harmonic frequency distribution of energy-saving lamps b. broadband broadband modulation .offset by ± 22.5KHz modulation sub-carrier frequency modulation, carrier frequency range of 2MHz-6MHz between commonly used in high-quality multi-channel transmission system for high-quality simultaneous interpretation, language training, wireless tour guides ., multi-channel movies, hi-fi systems and other infrared transmitter. .Broadband modulation if the frequency interval can be distributed 200KHz up to 32 sub-carrier emission band. . The carrier frequency of 2.3MHz and 2.5MHz high-frequency have a strong anti-jamming capability, using ± 50KHz sub-carrier frequency offset mode, the frequency response up to 20Hz-20KHz, can be used for very demanding on audio quality .high occasions. .<TH Scope=col> </ TH> Figure 14 high-fidelity wideband modulation 7. RF transmission cable equalizer main RF transmission cable equalizer consider the following factors: c. transmission cable .Although the length of RF signals can be up to several hundred meters of cable transmission, but suggested that the first load modulator preferably infrared radiation from the nearest plate, and the whole length of RF cable bus link should be controlled in an effective .transmission distance. .In the same radio link, because of each IR emitter cable to the length of the modulator is inconsistent, when the relative signal of two infrared radiation plate significantly delay the arrival time difference, it will lead to the infrared signals in the region .conflict, causing some additional high-frequency noise. .<TH Scope=col> </ TH> <TH scope=col> </ TH> Figure 15 links the wrong way infrared radiation plate Figure 16 links the right way experience infrared radiation value is relative to the two infrared radiation board .modem connection cable length differences should not exceed 30 meters. .However, in the project implementation process, still there will be some special system wiring, the current design of some manufacturers have built-in infrared radiation plate to adjust the function of the RF cable delay, such as the DIS of RA 6000 series. . D. transmission cable terminal for the convenience of system wiring, most of the infrared radiation board all have RF loop output interface. .Whether in a radio link in the series with more than 1 table or infrared radiation plate, all links are the last of a radiant panel terminal processing must be to balance the RF signal power in the whole distribution chain. .Early termination impedance to 50Ω based, and now there have been a lot of transfer impedance of 75Ω termination. .Most of the infrared radiation board termination resistors are built through the toggle switch to determine whether the infrared radiation plate terminal processing, there are some new products with automatic terminal function, such as the DIS RA 6000 series. . 8. IR reception assessment <TH scope=col> </ TH> Figure 17 infrared terminal ??? Do not have the professional testing equipment in the case, you can use the following methods to evaluate the infrared receiver .effect: as right, with splayed fingers at 15cm away from the infrared receiver to block the infrared, if you can listen to the noise, then the region should install auxiliary firing board..

【 Weak current College 】 high-end audio products to buy---Power By 【 China power house network 】

With music equipment, as well as VCD in China increasing popularity of the family, the "home cinema" audio and video consumption is becoming consumers of new shopping hot spots, according to the Department of State Development Center market economy Institute of the household appliances market joint investigative research group in the last 4-6 months in the Chinese city of family and consumer electronics products on the market situation. Made by the 2003 China cities of home theater market research consulting report shows that in the coming years is expected to purchase the suite home theater system for the consumers in the total consumer 12.3% within the next three years of China's potential market size in about 650 million units. In such a huge potential market to attract, many AV products manufacturers introduce targeted video products, and quickly in the high and low line expansion. But for consumers when buying AV products are required to avoid going into three errors.

Blind pursuit of foreign brands

On the one hand because of the audio product market participants the spread of many leading brands, products, professionalism, on the other hand because of the number of domestic enterprises in technology as well as audio and overall production scale with foreign brands there is a large gap, therefore, high-end foreign brands in market share and market position are generally higher than domestic brands, however, because of the different manufacturers of products targeted for its market and its different its functional positioning with great distinction, because here, to purchase audio-visual product must first clear purchase standards and use the direction. You cannot indulge in blind pursuit of foreign brands, avoid high price that is a good product for consumer misunderstanding. Buy audio product process must consider many factors, sound effects only means that the audio equipment is best best. The sound effects are listening room size, room specifications, sound-absorbing structure and so on, from the overall effect of listening to determine sound good or bad. For ordinary consumers, in establishing the correct consumer awareness, to avoid the subject of "foreign" is a good consumer misunderstanding, it should be noted that the market price trap: the current domestic high-end audio products primarily to imported brands. Most of the imported audio brands in quality with high reputation and good quality assurance, but do not result in the buying process.

According to industry reports, because now the product purchase channels is more complex, some businesses adopt imported parts and then assembled on sale fashion. But the price is a homogeneous original official channels import product prices, this type of audio and video products in terms of quality, supply channels are hidden on, so the blind pursuit of high prices and foreign brands are purchase audio-visual products should be aware of and avoid the mistakes of the major consumer.

Conceptual misunderstanding: "home theater"

Home Theater: is the surround sound amplifier (or surround sound decoder and multi-channel audio power amplifier combination), more (4 more) speaker system, big-screen TV (or projection TV) and high quality A/V program source (such as LD, DVD, Hi-Fi recorders, etc.) with surround sound movie audio and video effects of audio-visual system. Since the current home theater in consumers ' perception of the unity of knowledge has not yet been formed, the majority of consumers now standard in buying a home theater of consumption is still based on the product's fuzzy concept. Part of the audio-visual manufacturers only in appearance and shock effect meet consumer demands and introduced a variety of audio and Visual products, resulting in a "home theater" cohabitation, brand range of products, also led to the consumers ' home theater product concept is more fuzzy cognitive. In addition, in the home theater hardware, such as AC-3, Dolby Digital, DTS, and other major names in use also tend to lack expertise of consumer confusion. Many unscrupulous merchants you grasp the concept for this class of consumers know little about the situation in product features exaggerated even confused as real ones, in troubled waters. Therefore, consumers purchase audio-visual products should be polished eyes, to protect you from unnecessary losses.

Blind pursuit of "home cinema" concept, easily in those exaggerated, in troubled waters by businesses.

Product performance mistakes

Speaker system, DVD player, and other equipment as the home theater of key components has been the focus of most concern for consumers, but since the majority of consumers buy audio products in the lack of adequate purchase purchasing experience and sound knowledge of such product in the purchase process will inevitably be businessmen and misled by the error cognitive resulting in unnecessary loss. Home theater speaker commonly used box material plywood, Particleboard, fibreboard, original wood. With plywood, Particleboard is typically used for low-priced speaker, and wood plank is usually imported famous brand high-end speakers can be seen, its price is expensive. Due to the current price of audio products, like product price brand, appearance, quality workmanship and other factors. From a few thousand dollars, expensive, several hundred thousand dollars. Product performance observation also exists on many misunderstandings.

First of all, due to the human ear can reach in 20-20000Hz, most products are difficult to meet this standard, the heavier part of consumers think that sound, sound, volume, the larger the better, in fact, the reasonableness of the fittings and match will also lead to serious effect. Amplifier and speaker selection of match is considered to be the focus, it has a direct bearing on music playback of effects and equipment life, according to experts, such as Japan's most power amplifier sound rather cold, hard floor, digital flavor is heavy, and only for some with a soft, warm tone of some of the speakers to match. If you use $ within the product, the same comparison the "cold" Germany speaker and accepted a "hard" by JBL, voice will be heard without resistance or badly, so spend more money effect will not be good. Consumers should understand the mix of knowledge, avoid blindly businesses recommended. In addition, the same price levels of different brands its sound effects also have greater difference, so often occur in high-priced purchase performance than low-priced products, learn about listening knowledge is necessary for purchase of home theater.

In addition, the DVD playback devices should avoid depressionInto technical mistakes. At present, the DVD market mainly in VCD disc player, DVD player and you can burn a DVD video disc types of mainstream products, since the DVD video disc in price, technical and ones are very mature, thus becoming an ideal choice among consumers. But because many DVD video disc manufacturer, product performance and functionality are relatively large differences, different grades of DVD player feature differences evident. Therefore in the purchase process should be based on the DVD Player user manual described features in one by one, and on the DVD player in a variety of terminals on the back panel and check the number of the interface, and should, as far as possible in the field of product demo to see the product in the functions are complete.

【 Weak current College 】 stage machinery safety design (3)

5. the necessary spare system or device
Equipment incidental result of a fault, to have the necessary measures to continue the use of (or in reducing technical parameters continue to use) equipment, or can make the device returns to a secure location. These measures include: auxiliary transmission system (electric or manual), multipoint transmission system, the computer control system and its components in a redundant configuration. The device comes with secondary transmission system commonly used in music pool lifts, main lifts, and multiple identical equipment auxiliary transmission systems, such as the boom winch room for boom winch of secondary transmission system, often is independent. Multipoint transmission system for alternate in the turntable, auxiliary lift and self-propelled vehicle platform more applications. In the computer control system, a number of important, more components such as the frequency use redundant configuration.
6. the provisions relating to the design data and
Due to the particularities of the stage machinery, foreign standards often design data for specific or different from the provisions of the General machinery. Although there is no specific internal design standards, but in recent years an increasing number of international exchanges, these provisions have also been domestic recognition stage machinery design units. These requirements are:
1) load: static load drawer unit with fixed table of static load is the same as for large and medium-sized Theatre 5000n/m2, the audience of load moving equipment are:
Lifts: 2500n/m2 (single platen or double-bed power Board)
1500n/m2 (double-layer bed down plate)
Train station: 2500n/m2
Turntable (with car turntable): 2500n/m2
Music pool lifts: 2500n/m2
Various secondary weight lifting table:
Bench equipment loads according to actual needs determine, no specific provisions on major equipment such as boom winch, track point crane, free single point lifters abroad are shaping product for design selection.
2) transmission device
Transmission (including the motor, gearbox, drive shaft coupling, etc) for calculation of bearing capacity should be the actual loading (or load rating) twice, the actual load is run in maximum load.
3) additional stroke
Under normal circumstances, the stage machinery of the total trip should include normal travel (by trip terminates switch control), hyper-journey (from the overtravel switch control) and extra trips. Additional travel means the overtravel switching action, before the stage machinery stop walk distance. Additional travel and machine speed and inertia, in General, the speed is less than 0.1m/s, extra travel 0.07m is sufficient. Speed is less than 0.02m/s hydraulic transmission, hydraulic cylinder with cushioning design, no extra trips. Balancing weight of extra stroke must ensure balanced weight and the supporting structure.
4) positioning and locking
Under device must be able to prevent inadvertent movement of the lifting device any possibility, wire, chain as bearing parts and hydraulic cylinder straight top without hydraulic lock or piston clamping device of the structure, you must set positioning locking device to ensure that the lift into the rest doesn't load after long-term effect and sinking.
5) brake
Each brake should be able to withstand all loads, brake braking force is accessible only by gravity or a spring force generation, with brake can be used for manual installations.
6) balance weight
Do not allow using spring instead of balance weight, balance weight should be installed in the frame and prevent the movement of falling out.
7) rope
Rope steel wire of the minimum nominal strength should be greater than or equal to 1570n/mm2, but if you exceed 1800n/mm2, mm2 calculation 1800n/.

Weak current College】【mixer use issues.

1 mixer signal input section need to be aware of the problem: it has introduced the input signal is generally divided into low resistance and high-impedance input, but how to define a way to signal is low resistance or high resistance requires flexibility. For example, in accordance with standard electric piano, electric guitar, etc. belong to the high-impedance signals, to use 6.35 plug can only be entered into the mixer, but in some places, from the stage to the connection between the mixer is too long, the line of resistance, together with the lighting system interference, so that the signal line background noise is very large, even if you do not enter any audio source signals, in a mixer on this line the input channels of the gain on metropolis has a lot of noise, as described above: this line is a river that now this river sediment has too much, nor is this line in the noise a lot or not convertible, and the line side of the instrument's sound volume is way up and no longer increases, the river can only give you the deep water, what should we do? if you are using high-impedance input signal is equal to the water in the river water is not without increased, sound quality can be changed, of course, no way to change; if you use the card you unplugged from low resistance Jack input signal, the river of shallow water will be after amplification of low resistivity amplifier so that the depth of water, water quality, sound quality is fine. That seems not quite true, everyone can try. I now do a lot of work, the band are all used the card Lennon interface from low resistance type, although not standardized, but is in fact reduce the band noise. So audio workers need to be flexible, pragmatic, practical search for the best way to work.

2. AUX sections need to be aware of the problem: I know there are faders AUX front/rear conversion, standards compliance, listens to signal to the stage with faders sent before, but in General or in the performance of which faders and sent. AUX signal used to listen to the stage as an example: I have two computers with AB CD machine took turns playing music, when A single music out I would pull down this road, you can turn off the volume faders sound, then the road B volume faders to push up. But at this point A single CD player could play disc, still in play, then if it is sent after using faders AUX signal, stage speakers, will not have A CD out of the sound, but if it is sent before using faders AUX signal, stage speakers will be the voice of A single CD sent, so the stage speakers up at the same time have A, B two CD machine voice, singer there is no way to listen to, although this time the master volume on the outside and is not affected. Therefore even send some author AUX auxiliary are also carefully adjusting.

3. Group allocation problems: marshalling areas need to be aware of the problem is quite simple, since all marshalling of volume can separate output without switching into the master volume, which requires the author to group the careful, for example: I used 5-6 Group to control the volume, bass sound mixer on most of the input channels of the Group 5-6 can continue, but if you are going to seriously, the microphone channel or press the microphone channel 5-6 Group produces bass sound feedback; it is now 5-6 group I have from behind the output independent output signal, and it is no longer passed the total volume output sound mixer, which is 5-6 marshalling to the total volume of the mixing console switches no longer pressed.

4, illusion power: most of the mixer will have within a 48 volt phantom power, which can be used to promote a variety of capacitor microphone, but because it is from the microphone line transmission of electric current, so always check the phone line, that line, otherwise the line contact when it makes a lot of current impulse sound. There is also a phenomenon that is: If you use a mixer with a battery of capacitor microphone, do not open the phantom power, otherwise they interfere with each other, make it rain "sand" in General.

5. recording input: most of the audio input channel mixer is a simple control and then directly through the sound mixer total volume output, so carefully, do not produce malfunction, suddenly the voice of the audio channel from the master volume on a mixer.

6, output level: the authors are aware of the standard level is recording 0dB, but actual performance generally exceeded in many or even reached + 10 dB, so don't see red light is a great start, but in real use, slightly exceeding the signal level is reasonable, then out of the sound effects are also the best. There is one thing to note is that when the peak indicator reaches + 4dB, rear and its corresponding output volume level before reaching 0dB 0.775 volts.

7, some functional buttons: in addition to important adjustment knob on the sound mixer are multi-functional knob, button, or switch, for example: positive and negative phase transitions button, high removal or low removal button, button, before and after conversion Fader Mute button, buttons, etc., some monitoring is often used by authors who are skilled, not often used in understanding the basis of its basic functionality, do not go to regulate them, lest we produce misoperation.

8, headphones and sound field effects: a lot like Master Chief has been tuned with headphones, headphones are very important, but the headset voice after all and onsite voice vary greatly, so I'm going to listen to the scene. Not unrealistic, wishful thinking to headphones as a point of reference, when you want to know in the sound recording, the headset can be used as a standard; in the scene when the headset is just a tool, but the standard is the author of the ear, to listen to the scene.

Where some of the important functions of a mixer and operational skills are also essential is said to have, there is one thing to declare: this technical article is to look at the broad underlying audio workers; those advanced theory, high-tech, let people see the clouds fog article is expert characters to the expert or experts look after all, the basis of! majority, they sound workers more need is easy technical articles!

Weak knowledge of audio and video