[linux-audio-user] Pulling off old 2-track reels and trying to slow them down

[Jack O'Quin]

Alan Taylor <alan-linuxaudiouser at lowb.org> writes:

> On Sat, 2005-04-23 at 08:44 +0100, Rob Fell wrote:
>> The most obvious reason I can see for this is that the effective sample 
>> rate is reduced to 12kHz via this method.
>> 
>> If you can increase your soundcard sample frequency, this should yield a 
>>   dramatic improvement (96kHz sample rate becomes effective 24kHz).
>
> That makes sense, but I seem to be having trouble getting JACK to run at
> anything above 48KHz.  When I start it at 88.2KHz or 96KHz, I
> immediately get messages such as "XRUN callback (xx skipped)", where xx
> is a number between 50 and 300, depending on which sample rate and
> frames/period I choose.  I get at least 50 skipped callbacks per second
> without doing anything but starting jackd.
>
> If I am not mistaken, the Delta 44 should be able to handle at least up
> to 96KHz.  I believe my kernel is set up properly since I can record 6
> or 7 tracks at 48KHz and 512 frames/period in RT mode for an extended
> period of time without any xruns at all.
>
> Any suggestions?

When you double the sample rate you generally need to double the
buffer size.  So, -r96000 -p1024 would be equivalent to -r48000 -p512.
Your latency is the same, either way.
-- 
  joq