On 10/30/2011 12:55 PM, Dave Stikkolorum wrote:
On 30-10-11 12:25, Jeremy Jongepier wrote:
On 10/30/2011 12:02 PM, Dave Stikkolorum wrote:
Hi,
I am a musician and programmer.
I use a laptop with an internal soundcard (intel)
and ubuntu studo.
When I see the qjack control settings window
I always see a 46.6 ms latency.
On a older Desktop computer with an internal ac97 soundcard
or an pci sweex (cheap) I have the same problem.
Reducing the sample period to 512 , reduces the latency, but
always ends up with problems.
My question is how to have a good studio setup
for recording (and playing midi in the background)?
Is it possible to better the performance with an external soundcard?
What are your experiences?
I also tried ccma an av linux, but the same problems.
Anyone suggestions?
Regards,
Dave Stikkolorum
Hello Dave,
46.4ms is the default JACK latency (1024 frames / 44100 sample rate *
2 periods). You can try lowering it by reducing the number of frames.
But if you get xruns then (buffer errors) then you may need to
optimize your Ubuntu install. You might want to look here:
http://wiki.linuxmusicians.com/doku.php?id=system_configuration I certainly will
read that, thnx!
And it's possible to get better performance
with an external
soundcard, especially compared to onboard cards and specifically in
the case of ac97 soundcards. The latter just refuse to work at lower
latencies (at least for me). There are quite some soundcards available
that yield good performance and that are compatible with Linux:
http://wiki.linuxaudio.org/wiki/current_audio_gear
That sounds promising.
For starters could you run cat /proc/asound/cards
in a terminal on the
laptop with the Intel soundcard?
cat /proc/asound/cards
0 [Intel ]: HDA-Intel - HDA Intel
HDA Intel at 0xdb320000 irq 47
Oops, sorry, I meant cat /proc/asound/card*/codec* | grep -i codec
But thanks!
How much does the processor has influence.
The lower the latency the more CPU that will consume.
For example I have a 1,8 Ghz Pentium 4 upstairs.
That will work, I'm using JACK with a netbook which has a 1,2Ghz CPU.
But then I quickly hit the limits of what this netbook is capable of.
But I can run a simple session using my Edirol UA-25 USB soundcard with
8ms of system latency.
I would like to use both. (one portable studio and one
upstairs)
That's possible, you're best choice would be USB then assuming not all
your machines have a FireWire connection.
Best,
Jeremy