【 Weak current College 】 (go) expert detailed professional audio troubleshooting MI-5---Power By 【 China power house network 】

(VIII), professional audio Exciter: audio actuator is actually a harmonic generator, use one of the psycho-acoustic characteristics of sound signals are decorated and embellished by an audio processing devices. Following that when using the actuator under need to pay attention to some issues and actuator is prone to failure: 1, although theoretically use good actuator can enable increased loudness sound system, while at the same time signal 10dB output level and system output power is not too much change, but we still do not carry excessive actuator tuning, or they may damage the amplifier and speaker device. 2. the actuator IN/OUT in comparison with and without the incentive of sound effects, many sound engineer can't distinguish sounds the subtle differences, because the speaker out of voice rarely direct radiation to sound normal ear, so pay attention to when adjusting to the effects of acoustic venue to listen, brazenly chaos tune may cause sound weird, microphone transfusion, serious damage to the device when you also. 3, there are some of the acoustic field smooth reflection area because there are too many in the treble of the sound system is powerful, sound reflection is also very noisy, and if you then join the actuator "penetrating" is even worse, the treble will become more harsh, loud, acoustic feedback may become unmanageable, and therefore, better sound field is very important, nor is any sound field using actuator. We can see that although the use of universal digital processor is a trend, but now the digital processors rarely with incentive function, most are: balance, compressor, crossover, delay, and equality. As a result of high-quality audio actuator in quite a long period of time or irreplaceable.

(IX), amplifier and speakers: what is a power amplifier-what is speaker I am not here to explain, here's that use power amplifier and speakers are required to pay attention to some problems and failures of these devices is easy: 1 match: generally speaking, the power amplifier power than speaker power, normally amplifier power than the speaker's power 30% or more, if you use small power amplifier to push power loudspeaker, amplifier easy overload, will produce the sound of the current, the driver can easily be damaged. 2, impedance matching: current professional audio systems using amplifiers are generally fixed resistance, general power amplifier at 4 Ω--8 Ω work up some audio masters like one amplifier push 2 more speakers, and then note the speaker impedance, many speakers and parallel impedance decreases, if less than 2 Ω is that this power amplifier is easy to damage the approximate short-circuit mode it is best not to use. 3, power amplifier and speaker line connection between: amplifier of signal cable to use balance line, if your system has more than one power amplifier, it is best to use signal amplification splitter divides into number enough, there is no attenuation signal cable supply each amplifier is used alone, this can reduce system noise, reduce risk, improve the SNR. Also note that the speaker cable quality and connection, as far as possible with relatively thick, short of the speaker cable connections must pay attention to distinguish positive and negative and avoid short circuit, especially the major four-core or quad-core above speaker plugs, several terminals is very small, it is also important to note that the wiring. 4. power amplifier behind sometimes many transfer switch, such as: mono mode, stereo mode, bridge mode, as well as the sizing of a level switch and signal frequency switch, etc., we use must be taken to see these transfer switch, the power amplifier adjustment to correct or you want to work, otherwise it may cause unexpected failures. Amplifier and speaker fault example: 1, 05 at Shanghai DJ contest audio equipment, our engineers said the bass is not enough, looking fore, I saw all the Bass Amplifier 130Hz low cut switch is turned on, the following are the bass 130Hzexcision, in this case there can be no satisfactory nature of bass. 2. once I a disciple in an outdoor performance, system of a total of four power amplifier, 2 QSC, 2 old masters of the United Kingdom recorded, signal lines through the amplifier rear input and output interface to convert distribution, according to the normal, formal approach to the entire system of power lines and signal cable is connected, turn on after system how did not sound. I used to have a look at mixer correctly, other former grade equipment is also no problem, then I put the audio signal separate input to QSC power amplifier and a voice in the speakers, a separate input to the old master of United Kingdom audio amplifier speakers also have sound, but when two amplifier via the signal cable is connected, the two amplifier driven by the speaker, all of which have no sound, I look at the discovery of the old masters of United Kingdom audio power amplifier with XLR card Lennon interface, 3 2 for the hot end, for the cold end, 1 = GND, and QSC and most professional amplifier behind you "connector XLR card 2 to 3 hot end, for the cold end, 1 = GND, because the signal port standard and standard, when the two amplifier of signal connections together, essentially equal to short-circuit, audio system, won't have a voice. Then I put the sound mixer 2 road in the main output signal to the QSC power amplifier, mixer 2 ch marshalling signals to the old masters of the United Kingdom recorded amplifier, the system is normal. Of course, I later discovered new audio guru power signal port is also adjusted to: 2 to 3 hot end, for the cold end, 1 for grounding. In short amplifier and speaker system is the system in the last two devices, the preceding is all peripheral equipment and services to them, in a project, can correct and reasonable connection configured amplifier and speaker, that the project is half the success.

Fourth, the device itself fault current professional audio equipment and most arevery ripe, general import of equipment under normal circumstances are rarely failed, but some domestic equipment relative to the device itself failed to comparisons, the following will introduce the professional sound equipment of common fault itself:

(A), the mixer often own fault: 1, volume faders contact is not good, the sound is choppy when working. 2-channel input port failure, such as previous old-fashioned Budweiser mixer of XLR input port card you can easily "uprooted", began to encounter this soWhen I really obstacles could not believe my eyes. 3. control system disorder, one time use a sound arts 16-channel mixer, and found that total output no signal, then later he changed to group the output, and so on down the marshalling and no signal output, but I pushed the 10-Channel faders, went out to do sections 11 road channel sound. Then I went through the AUX output signal, and so on, finally this mixer or thorough strike. At this point is the performance cannot silence, I simply put the CD signal directly to the power amplifier and drop some music. Failure of a mixer like this for so many years I also met for the first time, it had not heard of before. In short a mixer of fault simply enter part, output, control part, power part and so on, are typically caused by aging.

(Ii), Equalizer common own fault: 1, Equalizer sliding key contact failure, this is the most common, mainly due to aging and bad environment. 2. Equalizer inner line fault, I've seen some Equalizer only one signal output, later discovered that all the circuit broken, but this equalizer, I met several times.

(Iii), compressor, electronic dividers, professional feedback suppressor, professional fault delay unit common itself: these devices in addition to the severe aging equipment is generally not a big problem, the best is the adjustment knob and back panel signal Jack a bit small.

(Iv), digital effects common fault: 1, noise, digital effects when processing audio signal itself has some digital noise, if combined with the shielded signal cable is not good, serious noise like rain. 2, digital effects of core part is digital processing chip, the digital chip has failed, I saw one YAMAHA500 effects, able to splash but does not work, there's no way to adjust your all and so complex digital chips also didn't approach to maintenance.

(5), amplifier and speakers common fault: 1, power amplifier for most common failure is bad capacitor or burning power amplifier tubes, which we use, but most of them were not stable on the device itself. 2, then I also found some amplifier occur a channel no sound of fault, or inside the circuit. 3. as regards the other fault what amplifier volume potentiometer contact is not good, left and right channels are not balanced, protection features are too frequent, back panel work transfer switch contact bad and signal Jack, in short, the power amplifier is now sound system easier for failure of an electrical device. 4, speakers section of the fault of the most common questions is, of course, the Horn can be said to have a sound system in the most vulnerable to failure is burned Horn, this of course, some people are factors, but most still sound quality problems. 5, speakers of another common failure is the wiring port aging, bad, and in particular the regular flow of speakers vulnerable to this kind of failure. Above these devices themselves failures generally sound engineer is no way to repair, in the previous article I said, the audio Division to achieve the "professional", if what power amplifier is broken, Horn bad those are maintenance engineers, our sound engineer's job is to match a good sound system, the various sounds good, doesn't have to be jacks-of-all-trades!