[LAU] Some Problems/Questions (about jack , qmidiarp and maybe other)

[John Anderson]

On Sat, 2008-01-12 at 19:58 +0100, luigi curzi wrote:
> ciao/hello
> i use  some applications on pc with a updated debian unstable to make
> some beautiful electronic (:-)) music. i don't have external midi
> controller or some instruments, i only use my pc. i have a creative
> audigy es.
> 1) what configuration can i use in jack for best performance?
> now i use this command line:
> /usr/bin/jackd -v -R -P70 -dalsa -dhw:0 -r48000 -p256 -n2 -P -s -zt
> with a latency of 10.7 ms; is it important latency in my case?
> 2) when i use vsthost with wineasio and some vsts i have some xruns
> and i can hear some poppings? is it a normal problem?

The basic idea is that if you're hearings pops (xruns) either you need
to run jack with a higher latency, or you need to look at an rt (real
time) kernel.

Low latency is necessary if you are using a midi controller to drive a
synth on the PC, or if you are recording and you need to do software
monitoring.

> 3) as midi arpeggiator i try to use qmidiarp (gpl but old, it is a dead
> project?) and hypercyclic (freeware, new and very good) but i can figure
> out how can use these softwares? precisely i don't know how link these
> programs with jack.

For an audio program to support jack, the programmers need to use the
jack api. Or if the programs support alsa but not jack, there is an
alsa-jack plugin (or whatever it's called).

bye
John