[linux-audio-user] recent hydrogen / jack / ardour

[Mathias Lundgren]

lördagen den 25 oktober 2003 15.28 skrev Mathias Lundgren:
....
> I've run hydrogen feeding it midi via MusE and jack as audio output. When
> using -p 512 it sounds OK, even though it's possible to hear that the
> timing isn't accurate. When increasing the period, -p 2048, it's really
> horrible. I've glanced at the midi input thread sources in hydrogen and
> noticed there are a few mutex thingies there. I've tried increasing the
> real time priority of the midi thread, with no luck. I guess jack's
> callback function (audio processing) and midi input thread are locking each
> other out, and when the buffer gets bigger it results in greater
> inaccuracy. When running hydrogen with alsa output in the same scenario as
> above, there's no timing problems (but then I can't use it together with
> any other apps). The above scenario applies to Zynadd as well.
>
Correcting myself. I've run both zynadd and hydrogen fed by muse, with muse 
running without audio at all, or jack output. zynadd & hydrogen using Oss. 
Zynadd runs like a clock in both cases (muse w/without jackaudio so the 
problem shouldn't be MusE's midi-feeding), when it comes to sync, but 
hydrogen doesn't. The inaccuracies in hydrogen are even worse with jack with 
large period than with hydrogen using the Oss-driver, but there are 
inaccuracies even when running hydrogen with Oss, when fed midi from muse.

/Mathias