[linux-audio-user] Newbie Questions

Hi, just spent a month getting a linux audio workstation going and I've got a load
newbie questions I have'nt been able to solve, or find answers to; some technical, some bigger picture :

Machine Specs
-------------
Uniwill 340s2 (Advent 5480DVD) laptop
384Mb RAM
PIII 800Mhz (8 speed steps)
SIS 7018 Integrated sound chip
Chipset mostly SIS I guess.
40Gb HD (Fujitsu, recent model)
(Yea I know it's a piece of junk but I could write a heafty tome about my money situation at the moment)

Software
--------
Win2K NTFS 20Gb
NTFS 10Gb
Fedora Core 2 + CCRMA (everything from rpms), CCRMA Low latency kernal latest stable (2.6) ext2 10Gb
Rosegarden4-1, built from source

Hokay,
1) I boot up the low latency kernal everything is fine until I run a midi app. The machine has no physical ports but presents an input port and 5 output ports in Qjackctl (SIS7018,trident driver). I think the first is raw, then Midi0-3. The clearest repeatable falut I can give is when I run Qjackctl, with jack either running or not running and try to connect to one of the SIS midi ports, the machine freezes when I connect (Caps lock does nothing). Why would I connect to one of these ports you ask ? Well I don't but some apps do it automatically (rosegarden, Kmid) and this has the same effect. Can anyone tell me how to fix the driver or just get rid of the midi ports in alsa (or any other part of the midi chain) so that apps don't try to connect to them ?

2) I have no modules.conf or conf.modules. tried creating them, putting stuff in them, all sorts.

3) Should I be building all my own software for i686 ? Most of the CCRMA stuff is i386 I can't remember at which point the 'big change' in intel architecture happend (was it 286 got protected mode or somthing). Anyone give me a ball park performace improvment percentage for rebuilding the music software ? Which leads me onto ...

4) Rosegarden. Without any midi tracks, or the low latency kernal, rosegarden was starting to grind along (Full CPU load) with 6 audio tracks (48K), no effects or anything. Is it possible to do anything useful (say 10midi, 10audio + usual effects) in rosegarden with my machine specs ? Has any one got a recent good spec machine which allows them to do this using rosegarden. Has anyone done this with Muse, should I switch ? Rosegardens code is really pretty but is it fast ?

5) Latency. Is there any way to do things in non-real time ? Other than realtime monitoring (which I'm happy to go without) is there any way to pre-render stuff and put up with a pause before the music starts ? Am I right in saying that if you have 30ms latency, and you record a track, no compensation for this latency will be applied and the track will be 30ms late ? Is there any time stamping built into jack/alsa ? You know what I'm getting at, have I miss-understood somthing ? For my 2c worth, as a drummer (amongst other things), you may not be able to hear 10ms (low latency, with your snare going through some effects), but you can feel it. It's THE difference between 'energetic' and 'Chill out' tracks.

6) When I plump for a new box, should I get multi-processor.

I've got no internet connection and have to go to the public library and download everything onto my 128Mb mp3 player at the moment. (Incidently if anyone in a similar position, I've got some tips on using yum as a package manager)

Any help (especially with the driver problem) grately appreciated, I'm nearly there !
 
Received on Sat Mar 19 16:15:04 2005