I use a GK MB150S combo--have done for many years--great amp. Am I correct in thinking that if I used two separates (Amp. head and a 15" speaker/cab.) I would get a more 'fatter' sound? The style I play is jazz. Is there a difference between Bass Guitar amplification & amplification for D/B?---difference circuits used? What amplification do you use?--and have you used anything that you did not like? Your expertise appreciated.