【 Weak current College 】 sound engineering system debugging method

Sound engineering for debugging is generally divided into system debugging and debugging, where the sound introduce system debugging steps, the following system debugging step is generally use, to share with you.
Sound engineering debug step one:
System-level preliminary debugging
1. line checks in accordance with the system configuration of connected drawings, carefully check the line connection, verify that there are no problems.
2. the initial state to set the device power amplifier input is set to a minimum, include all peripheral equipment of input and output knob is set to 0 DB position or intermediate position. Follow the former to back-order power (to not open the amplifier), check that all equipment power normal to the amplifier power.
3. preliminary check system status right turn up the amplifier gain control, CD in a familiar music and adjust the input level to basic mixer in the normal position. Slowly push up a bit mixer faders, listen to speaker sound properly and that it is distorted, if not properly shutdown check immediately.
4, speakers and system polarity detection system basically normal, open all device power, reactive power discharge flat set at maximum, pull down the audio mixing console output faders, phase meter generator access mixer input channel, open phase meter power adjust the output gain and mixer input gain to a mixer indicates the table is 0 DB. Slowly push up mixer output faders, speaker of the "bang" sound to reach adequate loudness (loudness is insufficient, the test results are sometimes inaccurate), phase meter detector checks whether each speaker and the speaker phase or the specification of a description. When it is best to close other detection of speakers to prevent interference detection and more accurate, one by one. If you are not working properly, check the speaker cable is reversed or system connector is inverted. Switch or replacement and testing.
5. phase adjustment if you also use the SLF and wide-band combinations, because of the existence of crossover system as well as the installation location, there may be a crossover frequency interference or delay time different problems caused by phase, so you will need to phase adjustment. Pink noise (PINKNOISE) generator received a mixer input channels, adjust the level to normal position and phase meter test microphone is placed in the middle of the venue, and the location of the sound into equilateral triangle. Push up the mixer output faders, check the spectrum analyzer screen in full-frequency and low frequency sound frequency frequency bands are there near the Valley of the point appears. If you have to upgrade the corresponding frequency band equalizer, if upgrading is not, is there a phase. A phase problems have a direct impact on the quality and use Equalizer simply resolved. To resolve the problem you need to adjust the phase divider of phase angle or the delay time between the speakers. Adjustment, look at the Spectrum Analyzer display, first adjust the low frequency divider phase angle to see if it needs to improve, if you have improvements, determine the best value and then adjust the delay time, delay time to adjust to the situation, if the low-frequency speaker distance seat near, you will need to adjust the bass be delayed, is also a look at the spectrum analyzer screen, adjust the delay time to try to ping the curve. The phase noise reduction to a minimum.
6. frequency balance in finished the above adjustment, you need to adjust the system's frequency response curve. The spectrum analyzer test microphone is placed in the seating area and a place to play the pink noise, watch the Spectrum Analyzer displays, defective parts, using the equalizer. And then to test the microphone placed in different places, then, in turn, transferred balance, many changes in several locations, repeatedly adjusted balance so that all regions of the frequency response curve as possible straight, even if the equalizer is generally good. [fenye]
7, dynamic control device regulating General dynamic adjustment of equipment is the compressor, limiter, if that is the concatenation of chain connection in system, are generally used as a protection system, mainly use compression for limiting functionality. Limiter settings I normally do: compression is set to passthrough (BYPASS), input/output gain set to 0 DB, the compression ratio is set to "Infinity", then a mixer send pink noise signal, gradually pushing large observation power amplifier input level indicator, indicator is lighting if the clipping indicator (CLIP) is lit. Access to press for the adjustment knob, so that the start level power amplifier input clipping indicates off. Then put a mixer output upgrade 6 DB or give output level led to + 6 DB, then emphasise that start level so that the power amplifier clipping LEDs just start blinking. At this point, system-level debugging is complete, as for the sound tuning and effect processes (including effects, Exciter, etc.) generally belong to the tuner to the task. Of course, in sound engineering, which is normally provided by audio company technicians to do.
Acoustics adjustment step 2: avoid whistling and singing microphone sound of debugging
① listening system as the first step inside of fine a microphone level, without the microphone mixer, mixer channel push evenly on the 0 DB position (if you listen to the stage from the faders of the signal is output after the secondary). Microphone on the stage the main location, open the monitor output control (AUX) gradually pushing up output, caused a band such as microphone screech, spinner knobs make Whistler AUX stabilized at a volume level, then adjust the equalizer, make this band of Whistler, and then continue to increase volume, and so another band of Whistler produce, then adjust the equalizer, and so on, and so a mixer output level knob and push rod or AUX to normal position (0dB), the microphone is no longer producing howl, OK, pull down the audio mixing console fader. This method is used to find out the venue can easily lead to resonance of Whistler, then appropriately lower microphone channel level, find someone who came to speak to the microphone, and then gradually increase microphone volume to the normal position, if there are whistling, then by the equalizer. Action: be sure to control the level, so that after the emergence of Whistler can maintain a steady level and then adjust is more accurate. Operation must be slow, or a call, there is no way one by one to find the correct point of Whistler. Room resonance point generally in 5-6 points, if feedback point too much, it is necessary to check the speaker set-up is reasonable.
② the primary sound reinforcement system transfer finished listening screech, then follow theThe same way to regulate main sound reinforcement systems, if the primary sound reinforcement is two-channel system, first turn off a single channel to push a mixer input faders, gradually increase the volume to find whistle points. Tune a channel, turn off the channel tune another, both fine, then put two channels at the same time push up then check whether there are other Whistler point, again by the equalizer.
2, in Whistler once the issue is addressed, the regulation of a microphone sound
① vocal microphone with a higher quality of the microphone as a reference (I recommend using SHUREBETA87A), adjust the microphone input channel equalization, make use of the microphone's sound as close to the reference in the high-quality microphone, detailed methods see I used to send messages. After you complete this step, the microphone sound General can meet the requirements of most of the actors, and then let the actor auditions for the microphone, press the actor's request, to the sound mixer Channel Equalization do some fine-tuning.
② plus microphone adjust the original sound effects, can the reverb effect with joining, to choose the appropriate type of effect, open the mixer's output, corresponding to the AUX also adjust the input level and the effects sound mixer auxiliary output level, on the phone, look at the output to the signals of the effect is too large or too small, in general this signal control to 0 DB. Effects mixing ratio is set to 100%, then gradually turn up the effects of the output level, detection output back to the mixer level is normal, if normal, gradually increase the effects of the knob, according to the return of the actor's request, the amount of the effects set to suitable level. Add effects, due to the existence of artificial reverberation can produce new Whistler, General easy in the first low-frequency whistle points, good for returns is access to the line input of the sound mixer, you can adjust the input channels of balanced to eliminate whistling. Soundman comments: as a regular audio engineering company, is equipped with professional testing equipment and I think it is very necessary, after all, many of the objective of the specification is not able to rely on the ear to resolved, the use of the instrument can be quickly and accurately for proper debugging. Of course, a lot of friends who are engaged in live debugging does not have the conditions, if you do not use instruments, many people believe the ability to listen and feel that there is a certain defects, experience accumulation of subjective judgment be used as a reference, after all, people and human feel different. Long term field tuning friends have enough sense of listening, if properly understood, the same effect can be improve debugging, but only if you have a profound understanding of the equipment of various objective specifications in various sound fields produced by change. Subjective listening debugging based on an objective basis to the specifications, which allow you to maximize your tuning capabilities, the device's advantage to thoroughly.