Due to just how important these two things are I decided to take a few really popular posts and put the content in one thread. Links to these great threads can be seen here
http://audirevolution.net/forum/index.php?topic=4000.0
http://audirevolution.net/forum/index.php?topic=3950.0
http://audirevolution.net/forum/index.php?topic=3950.msg116391#msg116391
See next post for start of thread.