In the sound reinforcement system, if the volume of the microphone is greatly increased, the sound from the speaker will be transmitted to the howling caused by the microphone. This phenomenon is acoustic feedback. The existence of acoustic feedback not only destroys the sound quality, but also limits the expansion volume of the microphone sound, so that the sound picked up by the microphone cannot be reproduced well; the deep acoustic feedback will also make the system signal too strong, thereby burning the power amplifier or speaker (usually burning speaker tweeter), resulting in loss. Therefore, once the sound feedback phenomenon occurs in the sound reinforcement system, we must find ways to stop it, otherwise, it will cause endless harm.
What’s the reason for acoustic feedback?
There are many reasons for acoustic feedback, the most important being the unreasonable design of the indoor sound reinforcement environment, followed by the unreasonable arrangement of the speakers, and the poor debugging of the audio equipment and audio system. Specifically, it includes the following four aspects:
(1) The microphone is placed directly in the radiation area of the speaker, and its axis is directly aligned with the speaker.
(2) The sound reflection phenomenon is serious in the sound reinforcement environment, and the surrounding and ceiling are not decorated with sound absorbing materials.
(3) Improper matching between audio equipment, serious signal reflection, virtual welding of connecting lines, and contact points when sound signals flow through.
(4) Some of the audio equipment is in a critical working state, and oscillation occurs when the sound signal is large.
Acoustic feedback is the most troublesome problem in hall sound reinforcement. Whether it is in theaters, venues or dance halls, once the acoustic feedback occurs, it will not only destroy the normal working state of the entire sound system, destroy the sound quality, but also destroy the conference , performance effect. Therefore, the suppression of acoustic feedback is an extremely important issue that must be paid attention to in the process of debugging and application of sound reinforcement systems. Audio workers should understand acoustic feedback and find a better way to avoid or minimize the howling caused by acoustic feedback.
Post time: Oct-26-2022