Ardour is an open source, sequencing music editor... yadda yadda. Does some neat stuff, basically like an open source Cubase LE or some such. Handles a variety of plug-ins. There's info on the site as to how to set these up. There are problems with the automation and some other minute things on the Linux distro, but I haven't had time to run tests on the Mac bin to see if they fixed these or merely translated them right over for us: D You'll need Jack for it to run. I'm using Jack 0.100.1 and JackPilot 1.5.8, which are available, free of course, as a simple click-and-install bundle, or you can compile them yourself if you're bored. Simply open JackPilot, start er up, then double click the Ardour .app which you can get from
www.ardour.org. This will open X11 and you'll be ready to go. You'll need to spend some time reading up on the program though... if you don't, you'll spend a lot of time pushing buttons that don't do anything : D
cheers
-SP