1、 Adjusting distance method

Using a non directional microphone as close as possible to the sound source to pick up sound is not only an effective way to avoid screaming but also to increase the amplification volume.

It should be clarified that directional microphones (especially pointed microphones) have very little attenuation when picking up sound from distant sources, and adjusting the distance has little effect on increasing amplification volume and preventing noise.

Whether the sound reinforcement system is prone to screaming is not directly related to the sensitivity of the microphone. But high sensitivity microphones have sharp directional characteristics and are prone to generating noise. Reducing the distance between the device and the audience can actually increase the loudness of amplification. The total gain of the system can be appropriately reduced. If paired with a wide directional near-field speaker, the microphone can be kept slightly away to avoid whistling. Conference Room Sound System

For the direct feedback sound field of the speaker, the microphone should be as far away from the speaker as possible and the speaker should be as close to the listener as possible. The microphone should be placed behind the radiation direction of the speaker. If the microphone may be carried with you, the speaker should be placed near the microphone.

2、 Frequency equalization method

It can also be called broadband notch method, because the frequency curve of microphone pickup and sound production equipment is not an ideal flat straight line (especially for some poor quality conference room sound equipment), as well as the acoustic resonance of the hall sound field, the frequency response fluctuates greatly.

In this way, we can use a frequency equalizer to compensate for the sound amplification curve, adjust the frequency response of the system to an approximate straight line, make the gain of each frequency band basically consistent, and improve the sound transmission gain of the system. System.

Using equalizers with more than 21 segments, parameter equalizers can be configured in areas with higher requirements, and feedback controllers can be used in areas with higher requirements. In fact, when feedback self-excitation occurs in the amplifying system, its frequency is only fixed at a certain point of pure tone, so as long as a very narrow bandgap is used to cut off this frequency, the system can be controlled to scream.

3、 Feedback controller method

Also known as narrowband notch method, in demanding situations such as some live music, audio feedback automatic control devices are commonly used. This device can automatically track the frequency of feedback points, adjust the bandwidth Q value, automatically eliminate sound quality through acoustic feedback, and provide many protections. Its principle is to control through trap noise.