32 or 64

holstein
i have only 32bit hardware, and have not had a chance to use a 64bit linux distro yet... 32bit ubuntu and the software with ubuntu studio 32bit works well with my presonus firepod, and the apps i use most work great (ardour, jack, jammin)...

_guitarman_
I tried 64 bit Slackware and I quit it - not recommended if you need any apps that are 32 bit and don't give you the source - way too much hassle. It may be easier with other 64 bit os's. I'm on 32 bit slackware 13.0 with a generic kernel from kernel.org that I applied the RT patches to and I'm running a stable 32 bit Linux DAW. I have a PentiumD processor 2.8Ghz with 1GB RAM.

lsd
I'm running 64-bit vanilla Ubuntu at home, with a bunch of audio packages added on, and it works pretty well. I'm on a Core 2 Duo E8400 with 4GB RAM, so running 64-bit gives me access to all of my RAM.

The general desktop is fine (including Flash in Firefox, etc.), and all of the audio apps I use day-to-day compile and run flawlessly on 64-bit. 32-bit and 64-bit apps can happily co-exist in a JACK session, so binary-only JACK apps, like Pianoteq or the Loomer synths/effects, aren't a problem. Wine-based stuff for Windows VSTs is generally fine, too -- both dssi-vst (for running VSTs as DSSI plugins) and fst (for running VSTs as stand-alone JACK apps) work fine once you have them installed.

Where you run in to problems is with linking 32-bit plugins in to 64-bit apps. If you want to run Ardour with its built-in VST support (not something I've tried, but hey, maybe someone does!), you can't build Ardour as 64-bit, though in theory if you installed a 32-bit Ardour on your 64-bit system, it should run fine. The same goes for native Linux VSTs in a host like Qtractor.

The other problem spot is Pd-extended -- vanilla Pd is fine on 64-bit systems, but Pd-extended is a total pain to get running, and even then, it's apparently still not perfect. I never got it working myself, so I can't say for sure!