So I've been using a Crate BH220 head and an Ampeg 15" Classic cab for practice and auditions with pretty good results. But the Crate started having problems so I purchased the Backline 600 yesterday after seeing quite a bit of love for it here. I went to an audition tonight with the BL600 and the Ampeg cab along with my Fender p-bass. I dialed in fdeck's EQ and the result was very muddy with my Fender's tone rolled all the way down. So I adjusted all the BL600 tone knobs to 12 o'clock and still muddy. Had to turn my tone knob on my bass almost all the way up to get any definition and then the string "twang" could be heard. I know a 4x10 cab sounds better, but I was having no problems with the Crate amp. I use a Hartke 4000 for gigs, but was hoping to use the BL600 as well. Any suggestions? The music is classic rock/blues/Motown.