Ok, I never played any instruments before bass, and as of now, I've only used combo amps. Now, I was wondering about this whole stack thing. To my knowledge a stack is... Head Preamp Speakers and a half-stack is A head/preamp put together Speakers Is this right? If so, also what is a power amp? Is is the head/preamp put together? Also what is a monitor? I'd ask someone I know who's involved with music, but they'd laugh at me and probably point too.