Hello all, Core Sound <http://www.core-sound.com/default.php> willsoon be offering a tetrahedral (Ambisonic) microphone at a very reasonable price. They are also working on a combined preamp + AD converter unit for this mic. This will be able to multiplex the 4 channels over a single SPDIF link, by using it a the double sample frequency.
I'm currently working on a software controller unit for this microphone. It will perform A-format to B-format conversion, and allow measured impulse responses to be used for calibrating the four mics. The result should be a very high quality portable surround recording system at a reasonable price (compared to other solutions which cost easily five times as much). The remaining problem is the demultiplexing of the two double speed SPDIF channels to four channels. It could either be done within the ALSA layer, or in JACK's ALSA backend. Doing this in a JACK client will not work unless it would be the only client - all others would get the wrong idea of the sample frequency and buffer size. So here's my question to both the ALSA and JACK teams: what would be your idea of a solution for this ? -- FA Lascia la spina, cogli la rosa.