Can someone shed some light on the Beta series EQ section? I find it pretty difficult to work with. I've read that the bass and treble are shelving controls, so turning up the bass knob boosts all of the bass frequencies (20-400hz according to the manual) and turning up the treble boosts all of the treble frequencies (1.4kHz-20kHz). Does the mid control (400-1.4kHz) operate differently? It seems like it is sweeping the frequency range but also boosting, while the bass and treble are just adjusting the volume of their set respective ranges. Is that the case? And does the EQ just boost or does it cut as well? It's pretty finicky to set up, especially once I start driving to blend the channels...