Basics of Equalization and Feedback 

Equalization: Selectively boosting or cutting bands of frequencies to improve the performance of a sound reinforcement system.

What equalization can do when used properly: 

• Noticeably, but not dramatically, improve the naturalness or intelligibility of a sound reinforcement system by emphasizing the frequency ranges most critical for speech.

• Noticeably, but not dramatically, increase the overall output level of a sound reinforcement system by reducing the system's output in the frequency bands at which feedback occurs. These frequency bands will differ from system to system based on many variables, including room acoustics, microphone placement/design, loudspeaker location/design, even air temperature.

  What equalization cannot do:  

  • Make a poorly designed sound reinforcement system work satisfactorily. Every well-designed sound reinforcement system is subject to the laws of physics described by the Potential Acoustic Gain equation.
  • Improve intelligibility problems caused by reverberation, reflections, mechanical vibration, high background noise levels, or other problems caused by the location or physical design of the room. These problems are acoustical in nature and cannot be solved electronically. They must be resolved with acoustical solutions, such as sound absorbent panels and heavy drapes.
  • Improve intelligibility problems caused by the talker being too far from the microphone.
  • Improve the performance of substandard audio components in the sound reinforcement system.
  • Eliminate distortion or noise problems caused by mismatched audio levels between system components.
  • Improve echo return problems in teleconferencing systems.