Hmm, it would be a fun project then to come up with a profiler of various audio cards by recording and then capturing a specific buffer of audio data. Then by comparing them (assuming that this drift is constant) see how many empty samples there are (or if the playback is slower, how many samples are missing), and then create a framework that allows real-time resampling in order to compensate for that discrepancy whenever multiple soundcards are being used :-D Of course this would be relatively pointless as for any serious work one should always resort to a better card rather than experimenting with this. Nonetheless it may prove to be a fun project sometime down the road ;-) Best wishes, Ivica Ico Bukvic, composer & multimedia sculptor http://meowing.ccm.uc.edu/~ico/ > -----Original Message----- > From: linux-audio-dev-bounces@xxxxxxxxxxxxxxxxxx [mailto:linux-audio-dev- > bounces@xxxxxxxxxxxxxxxxxx] On Behalf Of Fernando Pablo Lopez-Lezcano > Sent: Friday, May 28, 2004 3:04 PM > To: The Linux Audio Developers' Mailing List > Cc: 'A list for linux audio users' > Subject: RE: [linux-audio-dev] re: [linux-audio-user] A bit of goodnews-- > paper now available for your viewing pleasure and/or comments > > On Fri, 2004-05-28 at 10:55, Ivica Ico Bukvic wrote: > > Hmm, so just for my own understanding of this, if let's say 2 soundcards > A > > and B lack sync between themselves, yet are being fed in appropriate > > intervals small buffers of audio data from JACK, what is preventing them > > from staying in sync? > > The slower card will have to be fed something other than the source > material from time to time to be able to catch up to the faster one (the > "source" is coming at only one speed from only one place and going to > two different places that need to be fed at slightly different rates). > The "something to be fed" will be probably silence, that is, a click :-) > The size of the buffer and the amount of drift between cards will > determine how often you get a click (if the software would support doing > this at all, of course). > > -- Fernando >
