[LAU] Jack vs. Alsa, PianoTeq demo: Alsa wins!

[Aaron Krister Johnson]

Hey all,

So the continuing saga is this: still no luck getting Pianoteq with JACK to
equal or spank with superiority the performance of PianoTeq w/ALSA alone on
my system.....

I found the following information: the info from the /proc/asound output
that Paul asked me to check out confirmed that at comparable settings, JACK
choked where ALSA smoked. I had ALSA down to a period of 64 and 3
periods/buffer (hardware bufsize of 192) at a sample rate of 48000. The same
setting of jackd ('jackd -dalsa -dhw:0,0 -r48000 -p64 -n3 -S') didn't agree
with Pianoteq....

So...here's my dilemma. I have a live show coming up where I'd prefer to use
the superior harpsichord sound of Pianoteq, but I don't want to risk a
lock-up or xruns or worse in a live concert. So I would have to use
ALSA...BUT....I also need to switch to playing a live kalimba through some
Csound effects right after playing a harpsichord, and Pianoteq under ALSA
will not stand for another app opening and sharing the soundcard like JACK
will allow (ALSA will block I/O).

So what can I do?

Best,
AKJ

On Sun, Jun 12, 2011 at 2:40 AM, Aaron Krister Johnson
<aaron at akjmusic.com>wrote:

> Hi all--
>
> I'm wondering if anyone else has experienced this:
>
> I'm considering purchasing PianoTeq, but I wanted to try the demo. It seems
> to work better with just the alsa driver than it does with jack, a reversal
> of the usual situation.
>
> I tested this several times by playing fast glissandi on the default piano
> preset. Each time, my little EEE-PC netbook under jack choked with xruns and
> a brief silence while PianoTeq 'reset' itself, but Alsa alone chugged away
> with no xruns unless there was an extreme amount of load....
>
> I'm wondering if anyone can comment on this. It seems odd, especially since
> the jack developers claim jack adds no latency by itself to the picture in
> any situation---so, do we have a situation where the code is better written
> for the alsa driver than for jackd? It seems we do, in this case....
>
> Best,
> AKJ
>
>
>
>
> --
> Aaron Krister Johnson
> http://www.akjmusic.com
> http://www.untwelve.org
>
>


-- 
Aaron Krister Johnson
http://www.akjmusic.com
http://www.untwelve.org
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