Jack audioserver on Pandora


mcobit

mcobit

Advanced Member
Joined
Jul 28, 2008
Messages
6,909
Anyone got a working version of jackd running on Pandora?


I would like to try some programs like http://freewheeling.sourceforge.net/ as i think the Pandora would be a great mobile loopingstation for beatboxing and loopperformances with some instruments.


I can compile free wheeling without a problem, but it complains about the jack server not being started. I can't start it though as it says something about invalid configurations.


The toolchain seems to have the headers in it, as it detects jack at configure stage.


I also tried to install jack-server with opkg, but that doesn't seem to solve the problem with bad configuration either.


Anyone has an idea?
 
I am just installing slack, and hope it will work this time, but I'd like to put it in a pnd, so I think I will have to supply the complete jackserver with the pnd. Oh well...
 
Jack (like timidity) is so critical with many audio apps, why not make a standalone version ?
 
I could try, but I don't know if it will work out.


I got jack compiled with qjackctl under slackware, as well as the program and fluidsynth, but I can't start it with alsa support, as the driver cannot be loaded. Also I don't get realtime priviledges. Not even when Using the rt-kernel or as root.


Jack can be started with oss backend and without realtime, but then I don't get the mic as input nor can I hear any sound when I connect fluidsynth to the outputs and playback a midifile.


I'll see, if ai can figure something out this evening. If anyone is experienced with jack and wants to try, please help me :)
 
Jack needs to be configured for jack-alsa, and will probably need to 'take over' linux audio while running, which means kill whatever is running on Pandora (wtf, I forgot: is it plain ol' ALSA or OSS on PandoraOS?) and then let Jack be the main audio routing option.


Then, set up alsa loopback devices so that any ALSA-needing applications can still have them, albeit with jackd doing the dirty work.


Probably there is something specific with the Pandora Audio devices configuration, also, that is not 'automatically figure-outable' by jackd; I am afraid I'm not much help without my Pandoras in front of me (left 'em at the office), but I seem to recall there were not just the standard hw:0 devices, but others too. Jackd needs to be told what they are, specifically.
 
Plain ALSA i think.


I'm gonna rebuild an new rt-kernel based on the latest OP git, with all cleanups from Notaz.
 
I have no clue what they all are. There is hw:0, /dev/dsp, /dev/audio, someotherhw:0, etc. None of them seem to be the microphone for example. I just got one stereo input and output.


I think it was some alsa on top of oss or oss emulation. Alsaconf for example doesn't find a soundcard at all.


Edit: Maybe I should add, that I don't have a lot of experience with audiostuff on linux, so every help is appreciated :)
 
Last edited by a moderator:
No oss. Alsa oss-compat.


Alsaconf may not report a card although there's one present.


Usually hw:0,0 is the output, and hw:0,1 the input.
 
Last edited by a moderator:
I'm currently compiling the new rt-kernel.


This time the patch perfectly match our latest kernel ^^.
 
Btw, is there a realtime group set up for users, who want to use the realtimefunctions?


I tried to add my user to the audio and realtimegroup but wasn't able to use the rt functions. At least jack said so.
 
Got jackd working in realtime with an external UA-1G USB audio soundcard.
 
Great! But not with the internal soundcard? I need to get that kernel and try again.


Thanks for your effort!
 
Yup seems there's a problem somewhere with the internal audio :/


I must have been wrong when i said i did RT before.
 
Used jack2, they have a bugfix for ARM and it runs great!

(something with 'alignment trap')

I have tried different settings but I got performance down to 21.3msec latency.

This with:

  • Frames/Period: 256
  • Sample Rate: 48000
  • Periods/Buffer: 4
Theoretically it should be able to go lower, but we need to find the best settings.
 
Last edited by a moderator:
Dos this mean, Rackarack for Playing Elekrik Guitar and Bass via a Audiointerface like the Rocksmith Cable could be Real??
This would be awesome..
 
You must log in or register to reply here.

Similar threads

Inferno's Reaper
DC power jack resoldering question
2
Replies
22
Views
4K
Inferno's Reaper
Inferno's Reaper
sirthunder516
Headphone output sounds muddy
Replies
14
Views
8K
Seamus
Seamus
R
ALSA issue: twl4030-hifi hw params
2
Replies
20
Views
8K
dreamer
dreamer
ssokolow
Need specs for the barrel jack adapter
Replies
14
Views
10K
ssokolow
ssokolow
H
Headphone Jack
2
Replies
23
Views
4K
Jarska333
J
Back
Top