[PlanetCCRMA] general question

Fernando Lopez-Lezcano nando@ccrma.Stanford.EDU
Mon Aug 22 11:46:01 2005

On Sun, 2005-08-21 at 05:58, "Alexander Carôt" wrote:
> Hi to all,
> In terms of audio delay I've been using RtAudio with PlanetCCRMA (FC3) for
> quite some time. Yesterday it was the first time that I measured the latency
> and found out that it is at about 16ms (!).

And this is with what settings in Jack? (frames per period and number of

> I recorded the direct sound of a mic to the left channel of an external
> sound recorder and to the right I recorded the captured output of RtAudio. 

So the signal paths would be:
signal -> extra PC
signal -> A/D -> jack -> RTAudio -> RTAudio -> jack -> D/A -> extra PC


One detail you may not be considering: the A/D / D/A stages will
introduce several milliseconds of extra latency. How much depends on the
chips themselves. 

Did you try connecting directly jack input to output, just to see if
your program (through RTAudio) is doing any extra buffering? 

You may also want to try to use the small Jdelay utility:

-- Fernando