The Advanced Linux Sound Architecture (ALSA) is a Linux kernel component intended to provide device drivers for sound cards.
- Wikipedia:Advanced Linux Sound Architecture
The Jack-Audio-Connection-Kit is a sound server for advanced use, and is generally used by professionals looking to record. Regardless it does support mixing, although to get non JACK aware applications to work, a plugin has to be provided. The alsa-plugins package will pull this in.
Also called JACK-mp, it is the next version of JACK, with support for multi-processors and for network audio.
- real time patches for kernel26
- schedtool/nice (with sound server)