Len Ovens <len-ODU3Ot18rIYsV2N9l4h3zg@xxxxxxxxxxxxxxxx> writes: > On Wed, Nov 22, 2017 at 1:15 PM, David Kastrup > <dak-mXXj517/zsQ@xxxxxxxxxxxxxxxx> wrote: >> >> What could the Jack abstraction be? Synthetic Midi signals could likely >> fit pretty well but probably cannot be delivered sample-accurate. > > Sample accurate? Channel status is one _bit_ at a time and is 192 bits > wide. That is, for one User Channel word or Channel status word to be > derived from incoming data takes 192 samples of time. So jack at 64/2 > has better MIDI timing... (taken from ebu tech3250 and tech3250s1 both > of which are free to download... unlike AES documents) Well, perhaps "CDDB accurate" would have been a better moniker. That's essentially what it boils down to. > I was unable to find how dat tape machines encode and send text and > marker information. Well, I'm up for experiments here. > What I could find suggestes spdif is meant to be 20 bit and so it is > possible the two least significant bits might be used for other > purposes or that the dat is actually still 16 bit and the whole lower > 8 bit byte may have information that would allow tighter timing. but > 192 samples is the frame rate for most things so I expect that is what > is used. Sounds likely. I'll do some 24bit recording and look for suspicious patterns, but I doubt I'll have much success. > With regard to more than 2 channels, any format I know of is not open > or free. Even ADAT requires (does it still?) licencing. Certainly > anything with the name Dolby attached is closed... that is the only > reason they exist. Ok, the format may be closed, but it still may be hand-me-through. Probably not all that interesting. -- David Kastrup _______________________________________________ Linux-audio-user mailing list Linux-audio-user@xxxxxxxxxxxxxxxxxxxx https://lists.linuxaudio.org/listinfo/linux-audio-user
