If you turn the HF driver off on the BB2 then the mids/treble sound essentially identical to the SC. The real difference is in the lows - the BB2 is deeper and tighter sounding whilst the SC has a bit more thump and a bit less depth. The SC feels more like a bass cab in the lows whilst the BB2 feels more like a really good PA system.
For most bassists the decision comes down to your treble preferences, so if you prefer newer strings, like to hear the full range of synth or fuss effects or play acoustic instruments, then the BB2 is the one. If you tune lower than low B then I'd lean towards the BB2 regardless. There's no difference in loudness.
Thanks Alex, I know you wind up answering the same questions over and over... but how would you say the SM compares to the BB2?
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