[Home Theater Network HDAV.com.cn] In those cases, the audio equipment will make a sharp squeaking sound? For example, when the microphone is close to the speaker, it will make a harsh sound. I think this question I want to use as much as possible to make the netizens understand. This harsh sound is called "howling" or "feedback gain." The reasons for this phenomenon are as follows: 1 The speaker has a peak at a certain frequency in the sound characteristics, such as the following figure. The peak in these three red circles is the root cause of howling. What happens to the peak? The microphone will receive this peak continuously, and the sound will continue to play back the peak. Many times a second, the peak will be infinitely magnified until the device is damaged. 2 The input signal is too large, causing the sound that is released to distort and causing howling. In the final analysis, it is still the first reason. Ok, this time is the time to say how to solve this problem. 1 Use a good microphone and stereo. Why do you say this? Because the sound and microphone are very smooth in the sound characteristics, this smoothing is not to say that his curve is straight. Instead, the waveform has an excessively smooth slope with a small slope. This will not produce a dressing filter and will not have a narrow band of peaks, and whistling will naturally occur rarely. 2 Do not try to be too close to the sound and do not point to the sound. This way, even a howling point with certain frequencies can be effectively avoided. 3 Use the equalizer to reduce the howling point that can be found by a few dbs with the equalizer, so that the makeup brush can become a smooth waveform in the sound curve. This also reduces the chance of whistling. Basically these attentions are sufficient in everyday applications. I will not say the whistling of the self-excited, this one is to have a foundation, and the other is to do a good job in the line, and there will be no self-stimulation. So I don't talk about inverting the offset and adjusting the phase. Keep in mind that good equipment is the foundation, and care and patience are also necessary. The sound system must be done by the sound engineer himself, and the staff should be diligent. More fresh and fun home theater information, please pay attention to home theater network (WeChat: cnhifi) http://, the country's most influential home theater audio player interactive media website. The Stainless Steel Pipe series including all types of Round Stainless Steel Pipe, stainless steel groove tube, Square Stainless Steel Pipe, solid and hollow stainless steel , can supply the normal market sizes and supply it with different material, like SUS 201, SUS 304, SUS316., etc. Stainless Steel Pipe Stainless Steel Pipe,Rectangular Steel Tube,Square Stainless Steel Tube,Square Stainless Steel Pipe Foshan Dinghan Electrical Technology Co., Ltd , https://www.dinghanelectrical.com