First, adjust the distance method

Using an omnidirectional microphone, where the microphone is as close as possible to the sound source to pick up the sound, is one of the effective ways not only to avoid noise but also to boost the amplified volume.

It is obvious here that directional microphones (especially pointed directional microphones) have little attenuation for distant sound sources, and adjusting the distance to enhance the amplification volume and prevent howling has little effect.

Whether the PA system is easy to whistle or not has no direct relationship with the sensitivity of the microphone. It's just that the high-sensitivity mic is spiky and prone to squealing. Shortening the distance between the device and the audience can actually increase the loudness of the amplification. The overall gain of the system can be appropriately reduced. If supplemented by a wide-directional near-field loudspeaker, the microphone can be avoided slightly away from the whistle. Conference room wall mounted audio

For the direct feedback sound field of the speaker, the microphone is as far away from the speaker as possible, and the speaker is as close to the listener as possible. The microphone should be placed on the back of the speaker in the radiation direction, and if the microphone may be carried around, the speaker should be placed where the microphone is not close to the speaker.

Conference room sound system engineering

2. Frequency equalization method

Also known as the broadband notch method, because the frequency curve of the microphone pickup and sound-emitting equipment is not an ideal flat straight line (especially some poor-quality conference room audio equipment), and the acoustic resonance effect field of the hall sound, the frequency response fluctuates greatly. big.

This means that we can use the frequency equalizer to compensate the sound amplification curve, turn the frequency response of the system into an approximate straight line, make the gain of each frequency band basically the same, and improve the sound transmission gain of the system.

An equalizer with more than 21 bands should be used. The parametric equalizer should be configured where the requirements are higher. When the requirements are higher, a feedback controller can be used. In fact, when feedback self-excitation occurs in the amplification system, its frequency is only a pure tone fixed at a certain point, so as long as a narrow-band notch is used to cut this frequency, the system noise can be controlled.

3. Feedback controller method

Also known as the narrow-band notch method, in demanding occasions, such as some live music, an automatic audio feedback control device is commonly used. The principle is noise control through traps. Conference room sound system engineering