hi martin,
good to hear you are on the road with your pd/alsa/jack now. i finally have my "famous soundcard" [HDSP] up and running without a hitch as well. in answer to your ?'s, i am also forwarding this to the PD list in case anybody there has similar ones:
Here's a quick question in passing. Do you run a script at boot time to start jack?
no. it is pretty CPU consumptive. try browsing the internet while a jack app is running, something like the XMMS player even, and you may hear lots of hiccups. better to run it when you need it. type: jackd -d alsa -d hw in a terminal window [and make SURE you are not root when you do this, or bad stuff will happen!] then CTRL+C in that terminal window will stop jack. type: qjackconnect in another window to get the connection panel.
if you are using Demudi, it should have made a button in you menu to start and stop. otherwise, just make it yourself. since i use the Fluxbox window manager, i have the following lines in /etc/X11/fluxbox/fluxbox-menu: [exec] (JACK Start) {x-terminal-emulator -e /usr/bin/jackd -d alsa -d hw} [exec] (JACK Stop) { x-terminal-emulator -T "JACK Stop" -e killall -HUP jackd} [exec] (JACK connection panel) {qjackconnect} but if you use Gnome or KDE or whatever, you'll have to find where they go yourself.
also, note that i am using the 'jackd' command and not 'jackstart' command because the -realtime command that 'jackstart' gives isn't really working with my system [not recommended for kernel 2.4.20 with ext3 file system unless journalling is disabled]. maybe it works for you, in which case change jackd to jackstart in the lines above.
And what's a sensible place to put scripts such as one that launches pd with all the libraries?
that is what your .pdrc file does. it goes in your home directory. so mine is in /home/derek/.pdrc and it looks like this:
-blocksize 512 -channels 8 -path /usr/lib/pd/iemabs -lib Gem -lib zexy -lib iemlib1 -lib iemlib2 -lib iem_mp3 -lib iem_t3_lib -lib OSC
obviously, you won't be using 8 channels, and you may want to fool around with your blocksize if the sound starts glitching, but the rest of this should be alright, so long as your externals are in the right place... /usr/lib/pd/extra in my case.
then, by typing: /usr/bin/pd or even just: pd it should work out fine. you can also add this to your menu: [exec] (PD) {x-terminal-emulator -e /usr/bin/pd} and then you will have a button, if it isn't there already.
good luck! derek