Could you sync the sounds cards in software? If you feed an external 1 PPS into the unused stereo channel of each sound card, then you can solve both card-to-card phase differences as well as card-to-card frequency differences with simple software fitting after, or even while, samples are being collected.
I use the R-channel for my 1PPS timing, leaving the L-channel for analog input. A time-synced PC can resolve the seconds time-of-day ambiguity. Note that a sharp 1pps will give you 22 us (1/44100) precision. If you used a slower ramp'ed 1pps then software interpolation should give you sub-microsecond precision. If you want to measure the stability of your sound card, see: http://www.leapsecond.com/pages/sound-1pps/ Win32 source code to the tool is very simple; see: http://www.leapsecond.com/tools/1hz.c /tvb _______________________________________________ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
