[linux-audio-user] HDSPconf and sync
markknecht at gmail.com
Fri Dec 24 20:43:27 EST 2004
On Fri, 24 Dec 2004 14:29:46 -0500, Lee Revell <rlrevell at joe-job.com> wrote:
> On Fri, 2004-12-24 at 12:15 -0700, Mark Knecht wrote:
> > On 23 Dec 2004 21:53:34 -0800, Fernando Lopez-Lezcano
> > <nando at ccrma.stanford.edu> wrote:
> > > On Thu, 2004-12-23 at 20:11, Kevin Ernste wrote:
> > > > > Range 1 - 44.1K/48K
> > > > > Range 2) 88.2K/96K
> > > > >
> > > > > Jack can switch between either rate in each range, but for whatever
> > > > > reason it cannot switch between the two ranges themselves.
> > > >
> > > > Aha, this is precicely the behaviour I was looking for _across_ the
> > > > two ranges! As you say, sampling rates change happily within each
> > > > range, just not to/from rates in the other. In any case, I'm relieved
> > > > to know that it's not my setup (things are working remarkably well
> > > > now).
> > > >
> > > > I may contact the developer (if only to thank him) and inquire about
> > > > this, it seems to me that ALSA or JACK should be able to inform
> > > > HDSPconf of a rate change regardless of speed/range. It is
> > > > particularily painful at the command line where I'm jumping back and
> > > > forth between rates all the time meaning HDSPconf is always open ;)
> > >
> > > There was a thread long ago about this. I think the issue is that the
> > > number of channels that the device supports change with the switch
> > > between the two ranges of sampling rates. I don't remember why this was
> > > a problem.
> > >
> > > -- Fernando
> > >
> > >
> > Hi,
> > Yes - there have been two or three threads about this, I think. The
> > number of 'user visible' channels does change between the two ranges.
> > RME 'binds' two channels running at 44.1K to make an 88.2K ADAT
> > channel. The ADAT interface itself does not run at 88.2K. It's just a
> > logical combination of the data on both channels to make it look like
> > the card is runnign 88.2K. (Or 2x48K to make 96K)
> > Unfortunately this is not a globally supported mode of operation
> > for ADAT devices. None of the Pro Tools hardware I have supports this.
> > It does work fine between RME cards though.
> I also seem to recall there was some kind of an issue where you cannot
> distinguish an incoming 44.1 stream for an 88.2 (or 48 from 96) stream
> with half the number of channels, or something. This was either
> discussed on the list, or maybe in the comments in the driver source.
Maybe we cannot distinguish it but RME drivers can. I can set one to
auto sync and then on the other card tell it to be the master and
switch between 44K and 96K. The autosync end indicates the correct
I think it's certainly easier to know in advance which way you want to
More information about the Linux-audio-user