1. A lot of the "real-time kernel" aka "low-latency kernel" work
happens at Stanford University's CCRMA lab. Their home page is
http://ccrma.stanford.edu/planetccrma/software/.
2. For JACK there are some things you may need to do:
a. Install jack-audio-connection-kit-devel and qjackctl.
Qjackctl is a plugboard / patch panel for various devices and audio
sources / sinks. It's mainly a GUI but IIRC there is a command line /
config file interface too.
b. Add the user to *both* the 'jackuser' and 'audio' groups.
Otherwise you need to be 'root' to use JACK.