Pete, I'd agree with Rick's analysis. The LFE should be left at the base 0 setting. The bass, mid and treble controls are simply tone controls like the common bass and treble controls but having a much wider variety of adjustments. In general they should be left at the flat position unless you have a good reason to do otherwise. One situation that might call for adjustment would be with some pop recordings which are "hot", with an elevated response in the upper mids/lower treble around 2000-6000Hz. Although this is meant to sound more impressive on mediocre speakers, on accurate speakers such as Axioms, this sometimes brings complaints about "brightness". If you have any recordngs like that you could experiment with applying a few dB of cut to them in that frequency range.
