Distance-Based Automatic Gain Control with Continuous Proximity-Effect Compensation

Etter W. Distance-Based Automatic Gain Control with Continuous Proximity-Effect Compensation. In: AES Convention 133. Audio Engineering Society; 2012. Paper 8786. Available from: https://aes.org/publications/elibrary-page/?id=16528

@inproceedings{Etter2012_16528,
  author = {Etter, Walter},
  title = {{Distance-Based Automatic Gain Control with Continuous Proximity-Effect Compensation}},
  booktitle = {AES Convention 133},
  note = {Paper 8786},
  year = {2012},
  month = oct,
  publisher = {Audio Engineering Society},
  url = {https://aes.org/publications/elibrary-page/?id=16528}
}

TY  - CPAPER
TI  - Distance-Based Automatic Gain Control with Continuous Proximity-Effect Compensation
AU  - Etter, Walter
T2  - AES Convention 133
M1  - Paper 8786
PY  - 2012
DA  - 2012/10/06
UR  - https://aes.org/publications/elibrary-page/?id=16528
PB  - Audio Engineering Society
LA  - en
AB  - This paper presents a method of Automatic Gain Control (AGC) that derives the gain from the sound source to microphone distance, utilizing a distance sensor. The concept makes use of the fact that microphone output levels vary inversely with the distance to a spherical sound source. It is applicable to frequently arising situations in which a speaker does not maintain a constant microphone distance. In addition, we address undesired bass response variations caused by the proximity effect. Knowledge of the sound-source to microphone distance permits accurate compensation for both frequency response changes and distance-related signal level changes. In particular, a distance-based AGC can normalize these signal level changes without deteriorating signal quality, as opposed to conventional AGCs, which introduce distortion, pumping, and breathing. Provided an accurate distance sensor, gain changes can take effect instantaneously and do not need to be gated by attack and release time. Likewise, frequency response changes due to undesired proximity-effect variations can be corrected adaptively using precise inverse filtering derived from continuous distance measurements, sound arrival angles, and microphone directivity no longer requiring inadequate static settings on the microphone for proximity-effect compensation.
ER  -