【 Weak current College 】 sound engineering construction and commissioning and troubleshooting---Power By 【 China power house network 】

Sound engineering construction and debugging and troubleshooting
1. engineering technical characteristics: as professional audio engineering and technology are brought together many top subject knowledge in a comprehensive technology that along with the professional audio-related technology and development. Especially audio lighting equipment performance and quality, professional audio engineering technology of growing importance as a metaphor: professional audio works like a tailor in tailoring a dress, professional audio equipment like clothing fabrics, what kind of material on the market who can buy, but good Tailors can generally play the fabric to its greatest features, make a nice clothes, and even the best fabrics give a poor tailor, he can do out a decent clothes. Professional audio works is like this, the same cost, a different design, engineering and quality will be high and low points; the same equipment, different facilities, the quality of the project will also have high or low. To sum up the characteristics of sound engineering: engineering, engineering technology; engineering flexibility, but heavy responsibilities. To say that professional audio work, the technical personnel are aware: a medium-sized projects, hopefully a, 200 hours should be sufficient; a large engineering hundreds of hours of work and will also be able to complete, so compared to other sectors of engineering, engineering firm. But in this little project, contains a high technology content, require strict design and selection, you need qualified embedded, pipe technology; need reliable welding technology; need scientific means and so on debugging and testing, to say the flexibility of projects is also a strong, sound engineering objective constraints is not too big, but general users or decorative units as possible to meet the demands of sound engineering, but also the flexibility included significant responsibility, imagine; often hundreds of millions of engineering to construction, if you go up to the requirements or poor quality engineering, or even leave a project risk, and that has to bear a responsibility. 2. engineering technology as a high technology content, assume a larger responsibility of professional audio engineering in construction technology have special requirements. First of all, to have qualified construction team. Countries for the sound engineering construction must be efficient and reliable, in the absence of a qualified construction team, not just design cannot be effectively implemented, and construction quality cannot be guaranteed in this team should include: a related technology license electricians, welders and electronic technicians, etc., at the same time as possible is the number of audio engineering experience of personnel, such a construction team to ensure the project successfully completed. Secondly, the project must be in strict accordance with the design. Countries for the sound engineering is a complex project from theoretical design and construction technology of larger, if construction experience and imagination will certainly be reckless adverse consequences, and the design is fully aware of the various circumstances and after a series of calculations, you must become a basis for construction work. The last is, works must be in accordance with the corresponding technical specifications for construction. Sound engineering in construction are covered under a variety of types of work, these types of construction technology and security measures, only seriously implement these specifications, can guarantee the quality of the various construction link, can guarantee the construction of the safety of personnel, as regards the specific technical details and considerations, the author had in the audio technology, the magazine dedicated to describe here without further analysis. 3. construction of steps (1) first to pipeline and hook the embedded. Pipeline and hook components embedded in general need to determine the projects should start immediately after, as usually, the embedded line main is not to build stage, or no decorative surface Dolphin wall, if not be embedded in a timely manner, it is easier to influence the progress of the project, while at the same time must pay attention is embedded the export pipeline in collaboration with the decoration sector must be dealt with, or they may be due to improper handling of elegant decorating; hook for embedded location and hoisting strength must be architectural technicians confirm, security cannot be guaranteed, in General, need to be embedded in cement structures where the pipeline to select quality better steel tube, diameter according to the number of cables to determine; through the ceiling, decorative wall of the pipeline, generally choose iron or fireproof PVC trunking, mainly for threading the construction convenience, to accommodate the larger amount of cable, and fire prevention; long distance for the laying of the pipeline, it is important to set up at a certain distance, final inspection and repair is important to note that embedded pipelines work almost cannot be changed, once the decision about where, how much, how buried underground, and embedded it is finished, if you want to change it is unlikely that the embedded front must carefully analyze design unequivocally that the device number, position, power and control, on this basis, accurate line count, size and trends. (2) Secondly, for all kinds of roof rack for welding and installation. This work as possible and decoration project of cross, as in the construction of some holes in it opened and has been detrimental for ornament, decoration department is required to assist in the completion of the welding process, be sure to let workers with welding qualifications, how safe do in addition to the requirements, mainly welding quality is directly related to the scaffolding erection strength, cannot afford because welding construction and decoration are usually taking place at the same time, on-the-spot some inflammable materials, so it is important to note that in the construction of the fire, to be welded firmly, paint finish, you should start the installation, the installation sheds security also very important, there must be sufficient building technicians when to begin lifting; the last is that all installation parts must provide reliable protection measures, such installation is the only security guarantee. (3) then the following will make a variety of cable laying. 4, which although relatively simple, but it should also be careful, especially through pipes, tolerate a little sloppy, laying cable ethic to grasp method, for example, when the steel wire and tube dress to wear on the cable should be tied firmly, head to reduce resistance, rub a small amount of necessary lubricating oil; Secondly, the cable is damaged or disorder troubles; in addition to the cable laying down on the cable, as the skin isNo rupture, shielding for damage and whether the broken core and so on; and finally, be sure to do a good job of laying of cables on the obvious marks for installation and repair of equipment and in the future. (4) and then back to various equipment installation equipment installation must be completed in decoration, cable laying right after, as audio lighting equipment is not only expensive, but many devices need to avoid dust contamination, decoration project of messy scene is not suitable for installation of the device, device installation, first of all it should be noted that out of the box when you want to double check, because many foreign equipment for the packaging is very standard, there are some important spare parts or manuals may separate quarantine in the back of the box, easily together with the package when unpacking throw; Secondly, the device should be read carefully before installing the product description to master the correct installation methods, steps. For example, many computer light bulb and coated glass to wear cotton gloves are required, the installation does not allow direct contact with the hands; the last is the installation of the equipment must firmly, protection measures to complete, especially lighting equipment, location, weight and to campaign, General and on the stage or the floor above, therefore be absolutely secure. (5) last is power supply line, control line and the signal lines of connection. This is a need to specialize and technical work, so you should be good, responsible for personnel, in line, the first request must ensure that no power status, because audio lighting equipment of the power supply requirements, if at the time of installation to provide power, not only weak security, and are vulnerable to damage to the equipment; Secondly, compliance with the requirements in line with the electrical installation specification, because the electrical installation standard is whether a reasonable inspection methods, so the regulate standards of construction, the quality of the project reached period is entirely different, many in accordance with the specification of formal engineering construction experts knew work done "beautiful"; Furthermore, asks various connectors, large-scale engineering required to by two cores, three-wire, Lotus Connections, Lennon plugs, the number of multiple-core plugs from the large, often need a few people at the same time making a long time to complete, if you do not understand before welding the proper connection method and welding method returning from work, to be so cumbersome, so make sure you know, for example: European audio product card Lennon feet and General number, never welded;
Some light control cable shielded welding, if unreasonable, it is possible to make the lights produce malfunction; finally calls on the line all FireWire, zero line ground wire and shielded cables must be accurate, power supply, notably: sound and light of some devices use power to regular misunderstanding, for example: some devices use 110V AC, and random transformer is a separate add-in, if the connection lines when forgotten, but directly to the device's power plug is 220V power supply, you can imagine the consequences; for example: some with edge device uses a low-voltage AC power, and the use of low-voltage DC power, their plug shape is very similar, if not that, for the power-on light, resulting in the sound after RP-low-energy, sound pressure decreases, the consequences of poor sound quality, but also easy to cause the device shell live, leaving a safety hazard; from the shield, the system anti-interference ability of the network, mainly determined by the system shield is correct and the shield is not working, try to damage the device, and the power supply line phase error you may affect the sound of phase to be correct and shielding quality level, often found in a number of works: either no shielding or shielding layer formation-loop circuit; or shielded cable connection error no shielding network resistance does not interfere with, or even some construction personnel will signal and power of zero, ground, screened cable and signal wire this confused some essentials, casually connected, not only against the interference, but also bring about substantial interference, so be sure to first truly understand these concepts. (6) in addition to installation, power supply lines, connection checks. Because sound engineering's entire system of connection points and connectors, the installation also possible because individual reasons an error occurs, so that detailed examination is necessary, the General safety inspection including the installation of the equipment, the power supply line is reasonable, the connectors of the connections are correct, there is also an important check item is: carefully review each piece of equipment status set meets the design requirements, it must not be forgotten, otherwise easily cause damage to the equipment, these States include; amplifier in bridge, the bridge switch reset bit; various equipment of power supply selector switch is suitable; lighting equipment is computer-controlled; voice activation or lamp code is set correctly; projector input mode setting, and so on. (7) subject to the above steps are convinced that the construction is complete, it should prepare for device debugging. For commissioning, because each project is different, it is difficult to unify a generic method, the need for separate classification for discussion, if you want to completely and comprehensively on all types of project described the debugging process, the length is too great, the only general engineering equipment debugging simple. Debugging Preparation before commissioning of sound engineering, is a necessary skill and experience and requires careful and painstaking work of the spirit, when the design and construction will comply with the requirements, the debug unreasonable is not careful, not only failed to achieve the effect of design works, but also may cause the device to work in an unhealthy state. So in debugging before you fully aware of the importance of this work. Debugging carefully before you confirm each device is installed, is connected properly, the seriously to construction personnel ask construction legacy may affect the use of the problem; debugging carefully before you confirm each device is installed, is connected properly, the seriously to construction personnel ask construction legacy may affect the use of the problem; debugging must once again seriously reading all the equipment specification, carefully check the design drawings of dimensioning and connection methods; debugging before the supply line must be convinced and the supply voltage is no problem; debug locale not before; debugging corresponding to prepare before instruments and tools. Sound system debugging the debug sound system is a key project debugging, audio systems involvedAnd most of the equipment, the debugging part also up, problems may also be the most, so we should first concentrate on completing it. You need to prepare the instruments and tools: phase meter, noise generator, Spectrum Analyzer (with sound), Multimeter, etc. Debug: a separate post, gradually from the sources check signal transmission, this inspection is very meaningful, because only the signal transmission in various devices, power amplifier and speakers will receive a normal to properly handle the signal, they might have a good sound quality, so doing this work, we must be patient, be sure to carefully, to carry out this step, the speakers and the amplifier connected to the first-don't worry, the peripheral equipment is the best in bypass mode. Check where you want to follow the signal, when you want to follow step by step check signal going to gradually check its level settings, gain, phase and the smooth flow of information, ensuring that each device can be fore device provides the best signal, can provide the best signal for a subordinate, in checking the signal at the same time, it should also be gradually check its level settings, gain, phase and the smooth flow of information, ensuring that each device can be fore device provides the best signal, can provide the best signal for a subordinate, in checking the signal at the same time, it should also be visually equipment working properly and that it is stable, the significance of this work lies in the fact that a single device then fails or is not stable, easier to deal with, nor jeopardize the safety of other devices, so this check will not be brought into the next. The above is correct, you will sound and the power of exile a access system, in a smaller volume, using phase meter first check all the position box phase consistency, as the following debug ready to noise generator and Equalizer access system, ready for the Spectrum Analyzer to moderate volume begins on Equalizer access system, ready for the Spectrum Analyzer to moderate volume begins on balance on the equalizer Spectrum Analyzer to debug, test points should choose in accordance with the relevant standards, the equalizer debugging principle is: the Spectrum Analyzer to 20Hz ~ 20kHz audio, display in the halls of the frequency response curve in the test point of basic flat, note: on the point to test the volume you want to enable consistent, and record the balance of good debugging is the location of the point potentiometer frequency; similarly to a smaller volume and large volume, and then record a good debugging is the frequency of the equalizer; point potentiometer for smaller volume and large volume are additional debugging, then the equalizer debugging results recorded last several debugging results analysis data for a variety of volume amount all under balanced frequency of location, and then be tested and the frequency response curve portrayals Auditorium, the ultimate equalizer, the position of the frequency you want to record, note: debug the equalizer, mixer frequency compensation must be placed in the 0, other peripheral devices to the State, the other is in bypass is: in a typical sound engineering, taking into account the Auditorium of the decoration material absorption of high-frequency signal is weak, so it can properly be slightly above the signal 10kHz do decay. The above steps completed, you should conduct electronic dividers for debugging. Divider debugging can be divided into high, medium and low frequency separately, the divider in the system uses different. Debug methods are differentiated, if the divider is used only for the bass sound frequency, that as long as the equalizer debugging is complete, let the bass speakers work alone, the divider bass crossover point between 150 ~ 300Hz, appropriate to adjust the bass signal gain, feel the bass volume adjustment is available, and then, together with the full-frequency system, and then to hear the bass, and wide-band smooth volume; if the divider is used in the full-frequency system, requires accurate according to the speaker manufacturers supplied parameters Lou don't set high, medium and low frequency crossover points, and then repeatedly carry out band signal gain adjustments until the band sounds are more balanced, then the reference next Spectrum Analyzer in the test point of sound pressure situation further fine-tuning. Wait until the equalizer and e-modulus prescaler basic debugging is complete, you should begin the Auditorium sound pressure level of determination, the test points or some of the original selection, noise source should be pink noise meter, test in addition to full-band, as far as high, medium, low three band respectively select several frequency test, test goal is: the best dynamic signal, allows the system to adjust the sound reinforcement sound pressure at the point you want to achieve the design of the sound pressure level, at the same time to refer to high, medium, and low frequency points, then the equalizer and adjust a few electronic dividers, if each test point sound pressure level deviation of results, namely sound field uniformity is not good, they should be carefully analyzed and appropriate improvement, first from the architectural decoration of the construction process, if there is a large deficit, thus affecting the quality of the sound field, it should propose feasible measures: If there are no decorative obvious defects, or have certain deficiencies, it cannot be improved, you should inherit from the speaker set-up, and point to and installed form for analysis, the analysis includes speakers and four of the distance between the speakers, speaker installed location of the point-and-frequency characteristics and so on, the following is based on the actual engineering common speaker set-up, installation and use of diagram for a comparison. The following is the microphone and the effects of debug, debug for the microphone, you can use for classification, vocal wired microphones as long as there is no audible of line noise, sound quality good, the effective range of acoustic feedback can make use of the frequency spectrum analyzer for monitoring and making the appropriate frequency and location of records; musical instruments using wired microphone must and, together with the East team with debugging, and various musical instruments using the handset model and pickup distance records; wireless microphone must work together with debugging and bands, and various musical instruments using the handset model and pickup distance records; wireless microphone debugging should pay attention to: the antenna location and reasonable, and drop tube use appear dead point location (well documented), accept-signal level gain to fine tune the noise reduction can be adapted, the best place to look for again and again, for the effects of debugging, the principle is to ensure that the input signal gain can cause effects get better dynamic period of sound signals, and you want to have a certain amount of allowance, the effect of the mixed signal output according to the requirements set. As regards the effects of specific effects selectionAnd parameter setting, you should make some crude test, and then under programs require to selected, just a note: effects of reverberation time and delay of having a set of no more than a certain range, so as not to affect the clarity of language and signal continuity, microphones, and effects for debugging, should also include back to listen to the system of debugging, the principle is: let back to listen to the system's frequency response characteristics consistent with the primary amplification system, sound pressure level actors (including bands) can clearly hear their voice, not too large, you can create additional acoustic feedback, etc. For compressors for debugging, it should be in the system above the basic device set for, generally works, the role of compression is to protect the power amplifier and speakers, as well as the sound box and the sound of smooth, so when you are debugging set compression starting first level, usually don't set too low, certainly too high will reduce the protection function, specific settings should regard various compressors for adjusting range and signal, secondly to set compression boot and resume times, usually start time should not be too long, so that protection is not timely, the recovery time is too short, so as to avoid damage to the sound effect; then to set the compression ratio, General Engineering, 4: 1 set, the compression of the noise gate set to note: If the system does not have a large noise gate is closed; if there is a certain amount of noise, noise gate threshold level setting is low, so as to avoid the phenomenon of the intermittent sound reinforcement signal, if the system noise is large, it should be from the technical aspects of the construction, alone cannot resolve by noise gate, and other settings can be set according to the different requirements of the surface. Other device debugging a no longer a detailed introduction, in General, debugging, you must carefully read the product descriptions, gradually and meticulous fine-tuning, without undermining the fundamental sound field conditions, the selective use of audio processing equipment to meet the design requirements. Lighting system for debugging for complex traditional stage lighting system, as it involves people and stage lighting as well as different needs in lighting design, so that debugging including a light tone, color, color temperature, brightness, projection area, dimming platform scenes, sequences of editing, and other aspects of content that is not a general utility engineering can simple debugging, like sound system, also need to have a large number of serious debugging to complete, or as previously mentioned, for traditional complex lighting systems design, construction and debugging of the best in professional institutes and professional performance unit with the help of the General sound engineering light system debugging, due to both the performance of requirements not strictly professional venues, so debugging involves technical indicators, relatively light system debugging not too complicated, however, there are technical requirements higher than conventional stage lighting specifications, relatively light system debugging not too complicated, however, there are technical requirements higher than conventional stage lighting technology, that is: in practical audio engineering involves many computer lamp, so engineers should seriously studied. First of all, you should carefully check each device individually shipped condition, because the internal computer lamp control system and comparison of precision mechanical parts, lighting power power, protection measures are also relatively complete, so if for transportation or installation causes internal control unit or lamp bulb injury, computer generally does not work properly, but want to complex lighting system to confirm that the failed computer lamp failure cause more trouble, so try to connect to the system or install the previously separate check the status of each device, it can do is check the lamps and the purpose of checking the console. Second, we must correct the settings for lamps. It can be said that all PC lights to the correct settings to work correctly, so if you want to unit and system in normal state, the correct setting is very important, set includes lighting control, power supply, campaign coverage, lamps in the system address, control line terminal processing, in which the lamp in the system location setting in project frequent errors, it is set to the code of conduct, that is, when the dip switch on the lamp must be in strict accordance with product instructions provided in the table, not in haste. In addition to lighting control device for setting the maximum PC lamp is, needs to have appropriate, set the correct control device to control the operation, if the console improper selection, set unreasonable or fails, the computer lights not working correctly, or even working, especially complex lighting system control device in the light of work plays an important role and, therefore, must be set on the device, set includes control forms, control signal output mode, the lamp of the type and quantity of the contents of the control program software. Finally it should be noted that: in the above steps are completed, you need to check it again controller actions and the actions of computer lights are the same whether normal lamps of post, there are: it is necessary to pay attention to lighting and audio systems with each other without interference, if so, record the amount of time to produce stem and specific device model in order to facilitate future settlement. Video system debugging in general sound engineering, video equipment and the complexity are not too big, so debug looks relatively simple. First of all to set the display device. Because the installation constraints, it is often difficult to accurately in accordance with the requirements of the product on the distance to install, so when you debug the project needs to make adjustments to the display device and the settings that you can make the camera, edit the device debugging an accurate reference, General Engineering, display equipment adjustments mainly the adjustment of the projector, high-speed connection including: image distortion, high-speed, etc., is displayed for a multimedia have to row frequency and field frequency and field frequency adjustment, special note: the image distortion adjustment, if environmental conditions do not have, we must make full use of the projector's "inclined to vote for" feature to compensate, for example: RCF's 4001 projector has shown in the figure below: second to shoot, edit, and assign device debugging. Because the camera device in different working conditions and working environment, the image quality will have a greater differenceSo after the completion of the work should be on camera devices with adjustments, adjustments must reference the same display devices in the same scene under different light, adjustment of content including: head's scope of activities and control, the lens focus adjustment, white balance, sensitivity adjustment and the adjustment of the output format, and so on, edit, and assign device debug key including, adjust the signal input and output format, select the character format, etc. General debugging when debugging the system has been completed, respectively, and make sure all equipment in good condition, no obvious debugging not at that time, you should start the entire system of comprehensive debugging, and each system individually for each device to try different was that comprehensive overall debugging without clear specific tuning parts, its main tasks are run in the system, check their interconnected work part is to coordinate, check them in when you are working with will have mutual influence and interference, for example: check the video of the switch will bring the noise to sound system, check the audio system on voice-activated light control, check the lighting system of dimming action would interfere with the sound system and so on. System simulation run system debugging has been completed, the official must be running before the process is the system simulation run, no matter what the size of the audio system, the number of its units are relatively large, the status of work vary, coupled with the system equipment quality and stability of work inevitably uneven, in short works very hard to debug, hidden or found insufficient, but once the project is finished, an actual system running time, much more often over time, the phenomenon of overload operation, then the system already exist but have not been discovered vulnerabilities and weaknesses, it is possible to rapidly expand, to the user and works both sides adverse effects, the simulation run is to actually run in a similar environment, understanding the systems of work status, identify problems before they happen. It is first necessary to measure the system run independently and overall runtime of the phase of the power supply line. Although the design and construction of the power supply line for the corresponding requirements for the various phases of current assignments also has a broad understanding, but the actual operating conditions and theoretical value is sure to have access, in order to be aware of, foolproof, it must be on the actual run-time measurement of current situation, in general you can use the stream table clamp separation time, the number of running equipment respectively measuring, if you find that the actual measurement value and theoretical value has a significant gap, or the phase current allocation percentage gap is large, or line current extraordinary phenomena, you must reinstall the rectification, to ensure the safe use of electricity. Secondly to check each device to run at full load and the long-running work stability. Professional audio systems and non-professional audio of a large difference is their full load and the long-running conditions, the stability of the work, job stability is also very different from a professional audio lighting equipment of important performance indicators. But even with professional equipment, mutual work stability is also a difference is large, some equipment in very harsh environment still functioning, some devices are long working time worrying. These checks include: changes in sound, lighting control property changes, the wireless microphone frequency stability of the battery is not sufficient time to accept the situation, the device to work long hours when the noise situation, and so on. But it should be noted: the stability of the inspection work is to ensure that equipment is in reasonable condition, cannot be intentional in order to check the device working conditions or the equipment in a normal working condition, caused by damage to the equipment is not guaranteed. Finally to check each device to run at full load and the long-run time of fever. Sound system equipment are basically low power device that is running in must have varying degrees of heat, especially like PA, lighting, cameras, high power devices, usually of fever is more obvious, so a certain degree of heat phenomenon, will not use the equipment and systems, equipment of the security impact. However, if you install without retention appropriate thermal space, or the device itself in the long, heavy-load operation of thermal conditions, that it be addressed, otherwise light to equipment protection, to cause damage to the equipment. The normal working range equipment heating serious, be sure to replace the device; if you do not have the appropriate thermal space and equipment calorific capacity is large, you should consider the forced ventilation, and must explicitly tell users to regularly dust cleaning and maintenance. Also need to add is: generally in the simulation run for different loads, different time of the system, to further examine the system of security and stability. In short, system simulation run is very important is necessary, then each item in the work of will is device long running stability and security of the system work. In particular, the power supply line and heating equipment, will have a direct bearing on the project security, so you should cause all engineering and technical personnel. Debugging results and problems of records
Because sound engineering for commissioning, setting and checking the project a lot, but these results and problems is the future use and maintenance of important references, so needed in every step of the work will result and problem record, and then make the necessary analysis and summary. For users of useful log data, should be given to them for future maintenance of useful data, should be recorded by designers for safekeeping. Record results include: the device location number, equipment set state, debugging, test data, and related program to edit information, etc.; records including: equipment work environment, equipment problems, interference device health problems, and audio work unrelated but problems affect system operation, and so on. Engineering problems as a complex, technical types of projects carried out in sound engineering in a variety of problems that may occur, together with the acoustic light system types and quantity of equipment, and systems technical requirements also vary, so all kinds of problems are inevitable, often encounter some knotty problems. According to the characteristics of sound engineering, engineering design to project quality and progress play a major role, soAs long as the construction design and carefully follow the relevant specification, is generally not in the construction process have any problems, or that these problems will not be reflected in the construction. In most of the time, the engineering problems occur during the commissioning phase, or even use only after a certain period of time. Since it is a hard problem to solve is very easy, and often is the fee to check exhaustively for a long time, always persists; in later questions puzzling ourselves disappear, then I do not know when it happens, get people very headache, each engaged in sound engineering technical work will have varying degrees of experience. But while these problems is the variety of forms, but as long as the design has no errors, you can say there is only one of the roots, that is; construction of omissions. Therefore, even if they're difficult problems, or can be solved. The following is a common part of typical problems. (1) the device shell has charged phenomenon due to sound engineering work on all devices must use electricity, so debugging may first encounter part device shell live, although shell live does not necessarily affect the use of the device, but will endanger the safety of users, you must resolve. (2) audio system volume is insufficient project debugging when audio volume is always smaller and not reach the design of the sound pressure level requirement, it just goes to show devices in installation and Setup problems. (3) acoustic resonance and feedback occurs while in the design and construction is seriously considered, but inevitably there are not too comprehensive and unpredictable places, and that this problem will certainly influence the normal use, should be removed. (4) produce interference noise audio engineering experience interference noise a lot of time, cause vary, usually solving very trouble, but as long as serious analysis, from the system of construction is found on the analysis of the causes, gradually, the problem is resolved. (5) lights out in audio engineering and sometimes people occur lights motion does not coordinate, it shall not be subject to the control and the occasional mistakes, etc., although slightly out of control will not lead to great effect, but if the problem is not resolved a long time, the fault may be further expanded, while the lights of the malfunction in the performance of works not be tolerated. (6) PC lamp bulb often damaged while the lamp damage is normal, but if you use time is very short on corruption should not be is normal, especially computer lamp bulb prices generally more expensive, often replace will increase less overhead, better quality of life of the computer lamp generally should be 750 hours, if not durable operation failures cause the bulb to damage, use time below this requirement should be to find it. (7) video images not normal professional audio engineering video transmission distance is generally longer, usually signal will also need a video processing and distribution, and to more than one display device, the intermediate links also comparing multiple, possibly due to different reasons the video image quality is not good, affect viewing, so you should be processed. (8) wireless microphone sounds unstable now most sound engineering is equipped with a wireless microphone, but due to improper installation and debugging, a considerable amount of usage, especially in the performance, wireless microphone work will directly affect the quality of the performance, so this is a problem.