According to the professional audio equipment company, it is a very painful experience to encounter whistling when singing. I was originally indulging in the ocean of music, but suddenly the microphone burst into madness, and no matter how great the interest was, it disappeared.

Generally speaking, howling problem exists only in the sound reinforcement system, which is an abnormal phenomenon that often occurs in the sound reinforcement system. When using a microphone to pick up sound in a sound reinforcement system, since it is impossible to take sound isolation measures between the pickup area of the microphone and the sound reproduction area of the speaker, the sound of certain frequencies is too strong to cause self-excited oscillation of the acoustic and electrical signals, resulting in howling. . For howling to occur, three conditions must be met:

1. The microphone and the speaker are used at the same time;

2. The sound of the audio broadcast can be transmitted to the microphone through the space;

3. The sound energy from the speaker is large enough, and the pickup sensitivity of the microphone is high enough.

The hazard of whistling that cannot be ignored

Once the whistling occurs, it will cause the volume of the microphone channel to be unable to be turned up. After turning up the volume, the howling is very serious, which will have a bad impact on the live performance. When the critical point of howling is reached, the sound of the microphone will ring when it is turned on. Phenomenal sound has a sense of reverberation, which destroys the sound quality; in severe cases, the speaker or power amplifier is burned due to excessive signal.

It is not uncommon for the tweeter of the speaker to be burnt due to whistling, because in the whistling state, the strong signal will cause the power amplifier to clip (top-cut) distortion and generate a large number of high-frequency harmonics. If the tweeter cannot withstand such a Powerful high-frequency signals will cause the voice coil to be burned; in addition, in the howling state, if the output of the power amplifier is overloaded, it may also be burned.

How to suppress howling?

Howling is an acoustic problem unique to the sound reinforcement system, and it is impossible to completely eliminate it. In practice, audio experts have summed up many methods to suppress the howling of the audio system. By taking effective measures and using some electro-acoustic equipment, the purpose of suppressing, reducing and eliminating howling is achieved. The idea is to avoid There are three conditions for the sound system to whistle at the same time. Professional audio equipment manufacturers

1. Make the sound of the speaker not easily transmitted to the microphone.

a. Keep the microphone away from the speaker.

b. Decrease the volume of the microphone. If the volume of the microphone is too high, the probability of ringing will increase, so reduce the volume in time to avoid howling. In addition, if you want to hold or wear the microphone through the speaker, you should also pay attention to controlling the volume, otherwise it will cause serious howling due to the distance.

c. Reasonable use of the directional characteristics of speakers and microphones

Both the microphone and the speaker are directional. If the use position of the microphone is not in the radiation area of the speaker, the sound of the speaker will not be easily transmitted to the microphone. Similarly, if the speaker is not in the pickup area of the microphone, it will be difficult for the microphone to pick up the sound of the speaker. sound. Therefore, by properly adjusting the angle of the speaker, keeping it away from the sound-emitting area of the speaker when using the microphone, or keeping the sound radiation area of the speaker from overlapping the area where the microphone is used, howling can be suppressed.