James Garfield wrote:
> 
> A big problem I've been having consistently is that realtime audio is very
> choppy when I try to play any score.  Generating a soundfile and playing it
> back is clean; it's just the realtime output that sounds like garbage.
> 
> I'm using Csound for PPC, version 0.3.1, along with the Perf fix (all
> downloaded from the Mills FTP site).  I've checked to make sure that the
> sampling rate is 44100 all around, but that doesn't seem to make a difference.
>  Changing the audio buffer size changes the rate of choppiness but does not
> eliminate it.
> 
> I've got a 604e machine (160 MHz) with Sound Manager 3.3, from recently
> installing QuickTime 3.0....but I was having these problems with QuickTime 2.5
> and the previous Sound Manager extension as well.  At one point I had
> something like Csound for PPC 0.2b and did not experience these problems.
> 
> Is there something I'm missing here, like some preferences that need to be
> reset or tweaked?  I feel like a weenie whenever I do things the old-fashioned
> way and just generate a soundfile.
> 

Choppiness can come from two obvious sources:

- the orchestra/score are too demanding on the machine and it cannot keep up.
- the buffers (software and hardware) are not of optimal size.

You know the answer for the first problem. For the buffers, it is important to
change both the soft and hard (on the PPC, good values seem to be -b1024 and
-B2048. on Unix -b likes a small value...)

-- 
________________________________________________________
Jean Piche
Universite de Montreal
http://mistral.ere.umontreal.ca/~pichej
http://www.musique.umontreal.ca/electro/CEC/