[Home Theater Network HDAV.com.cn] Today is going to talk about feedback. What is feedback? We often see people outdoors holding a loudspeaker to promote or speak. When the microphone is turned on, the person has not spoken yet, and the speaker suddenly has a sharp scream, and the sharp noise suddenly makes the ear sting. This phenomenon is feedback.
The feedback Chinese is "returned", and some people translate it into "howling". The reason is simply because the sound is transmitted through the sound reinforcement system and then received by the radio equipment, such as a microphone, as depicted in the following figure: the sound wave is transmitted through such a loop to form a loop of repeated cycles, due to the environmental factors in the process. Some frequencies are continually intensified and, in the end, produce a lot of noise. Sometimes it's a treble, sometimes a bass.
Since we understand that feedback is caused by the formation of loops, we can eliminate the feedback by simply "blocking" the loop; there are many ways, such as turning off the amplifier, unplugging the speaker cable, and muting the microphone. But in the performance, we can't do this. So, is there any way we can prevent or take it in advance?
First of all, the main cause of the feedback is the microphone, so checking the position of the microphone is the first step. Many times, the chorus or singer on the stage, because of the acidity of holding the microphone for a long time, will inadvertently put down the hand, and the microphone just faces the stage to monitor the horn. In addition, pay attention to the position of the instrument's radio microphone to avoid directly facing the monitor speaker. The pickup inside the guitar is another accomplice to the feedback. Especially when the wooden guitarist finishes performing the guitar on the guitar stand, and the guitar ring just faces the stage monitor speaker, it is easy to trigger the feedback.
Solution? You can place the microphone on the microphone stand so that the performer can sing with the microphone stand without holding it. Then, attach the acoustic guitar to the ring cover.
If the above situation has been avoided, the number of microphones on the stage is not much, or even only one, or the feedback situation has occurred. At this time, the Gain (gain) on the mixer track should be too large. The oversized Gain increases the sensitivity of the microphone, allowing the microphone to receive too much audio from the environment, which is broadcast through the PA system and then received by the microphone. In this way, the playback is repeated, the audio is added and multiplied, and the feedback occurs. So reduce the amount of gain{gain} in your microphone, that is, the uppermost knob on the track turns a little smaller, usually the problem is solved.
In addition, when feedbac occurs, the common intuition that we often have in people's minds is to hold the microphone head directly with the palm of your hand. But usually this action will make the feedback more serious, because the action of opening the palm is like putting a reflector on the microphone head, but letting the audio concentrate more and more into the microphone.
Since the feedback is because the sound is repeatedly transmitted throughout the system, when we deal with the microphone problem, we can adjust the position of the speaker. Check that the stage monitor is facing the microphone that is receiving the sound. In some cases, especially in street performances, we often see the performer placing the main speaker behind their own. At this time, it is necessary to consider whether the diffusion angle of the speaker is covering the position of the microphone, so as to avoid "a feed cannot be pack".
The feedback is not terrible, and when we understand the cause, we can process it out in order. Feedback has a close relationship with volume setting management. If we can set the volume during soundcheck, we can reduce the feedback during the performance.
More fresh and fun home theater information, please pay attention to home theater network http:// (WeChat: cnhifi), the country's most influential home theater audio player interactive media website.
Bitmain is the world's leading digital currency mining machine manufacturer. Its brand ANTMINER has maintained a long-term technological and market dominance in the industry, with customers covering more than 100 countries and regions. The company has subsidiaries in China, the United States, Singapore, Malaysia, Kazakhstan and other places.
Bitmain has a unique computing power efficiency ratio technology to provide the global blockchain network with outstanding computing power infrastructure and solutions. Since its establishment in 2013, ANTMINER BTC mining machine single computing power has increased by three orders of magnitude, while computing power efficiency ratio has decreased by two orders of magnitude. Bitmain's vision is to make the digital world a better place for mankind.
Bitmain Antminer:Bitmain Antminer KA3 (166Th),Bitmain Antminer L7 (9.5Gh),Bitmain Antminer Z15,Bitmain Antminer D7 (1286Gh),
Bitmain Antminer S19 XP (140Th),Bitmain Antminer E9 (2.4Gh),Bitmain Antminer Z11,Bitmain Antminer S3,Bitmain Antminer L3+ (504Mh)
Bitmain Antminer,S19 Pro Hyd 198T,antminer bitmain,antin s19j,antminer miner
Shenzhen YLHM Technology Co., Ltd. , https://www.nbapgelectrical.com