Re: [Jack-Devel] Multiple latency across jack

On Thu, December 27, 2018 10:05 pm, [hidden] wrote:
> Is it possible to have different signal sources handled differently by
> jack ?

All jack clients run at the same buffer size.
I think you could make a client which stored multiple buffers and handled
the appropriate translation between buffer sizes, but I am not aware if
Pulse does this.  The pulse jack implementation has in the past been
described as not optimal.

> As an example, Mixbus uses jack directly  and runs at 44100 buffer 128/2

Do you need such low latency for Mixbus?  Increasing the latency would be
the simplest thing to check if you are having problems with under-runs.

> These other applications all use pulseaudio and I dont know if
> pulseaudio causes the overruns and resultant rickety sound.

Check the default sample rate which pulseaudio uses, and the sample rate
of the applications which connect through pulse.  PulseAudio will use
sample rate conversion when clients and default sample rate do not match,
that causes higher CPU usage and decrease in audio quality.

> I am really not familiar how pulseaudio works with jack. At the moment
> both pulseaudio and mixbus/jack outputs
> sound simultaneously  to the same output device without problem

The jack server requires exclusive use of an output device, so you must be
using the jack-sink client of pulse audio to send the audio to jack for
output to the physical device.

> Or should I find a way to send all these applications directly to jack
> for better buffer handling and somehow cut out pulseaudio ??

That would be the optimal solution.

-- 
Chris Caudle

1545971190.19000_0.ltw:2, <81793ce3375c9ac1ec4ba3b77db25ff6.squirrel at email dot powweb dot com>