AES Store

Journal Forum

Audibility of a CD-Standard A/DA/A Loop Inserted into High-Resolution Audio Playback - September 2007
10 comments

Reflecting on Reflections - June 2014
1 comment

Quiet Thoughts on a Deafening Problem - May 2014
1 comment

Access Journal Forum

AES E-Library

Extension of the Dynamic Range of Wireless Microphones

The dynamic range of the human ear is far superior to that of existing technical sound equipment. The equivalent noise level (CCIR 468-1) of the best microphones is about 20 dB. Peak levels of 120 dB and more are picked up with appreciable distortion. The microphone signal is transmitted by wireless frequency-modulated systems with a peak deviation of 75 kHz, and signal-to-noise ratios of up to 70 dB (CCIR-weighted) are achieved. At low sound-pressure levels the output noise of the equipment is about 6 dB greater than the microphone noise. At higher sound levels the dynamic range of the microphone exceeds by far that of the wireless equipment. Heretofore the idea of using a noise-reduction circuit was not practical. Existing circuits were considered unsuitable because of their physical size and power consumption. A new compandor integrated circuit makes possible a high-quality transmitter having the 10-mW radio-frequency output at 9V and 14mA, and operating down to 6V. The external circuitry for this integrated circuit has been improved so that it can be put to better use in wireless microphones. The dynamic range is extended to 82 dB. The system offers further advantages at low radio-frequency inputs, including suppression of electromagnetic interference.

Authors:
Affiliation:
JAES Volume 30 Issue 5 pp. 318-323; May 1982
Publication Date:

Click to purchase paper or login as an AES member. If your company or school subscribes to the E-Library then switch to the institutional version. If you are not an AES member and would like to subscribe to the E-Library then Join the AES!

This paper costs $20 for non-members, $5 for AES members and is free for E-Library subscribers.

Learn more about the AES E-Library

E-Library Location:

Start a discussion about this paper!


 
Facebook   Twitter   LinkedIn   Google+   YouTube   RSS News Feeds  
AES - Audio Engineering Society