I want to design and build a device which will take the audio output of several computers ,i.e. a mixer, and feed that output back to the audio inputs of all those computers. The result would be an audio bus. Anybody can talk, without switching, and all can listen. I would like to make it expandable such that 2 or more units can be linked together to connect more and more users. (15 - 20)
The application is for training of digital radio software and multi operator net operation. Over radio anyone can talk and all can listen. If two talk at the same time there is a collision and you have to back off and try again. I want to practice this with our sound card audio systems among several laptops in the same room. I would use this audio bus instead of a radio channel as the medium of exchange. Audio quality need be only reasonablly linear and then can be bandwidth limited to 5 kHz or so.
What would you recommend? Do you know of any products that do anything similar?How about mixers I could use as a front end, or audio amp that I could use as a back end?
As a additional feature I would add a headphone jack to each position so the operator could hear the combined audio bus in one ear and his own transmitted sound in the other ear. I would want to silence my receiver while transmitting.