Hi, I'll keep this short.

I have been using combo amps for my whole guitar and bass playing "career" so i know my question will probably make me sound stupid.

My biggest question is: I am buying a 1200 watt bass cab and a head (same brand) but the head is only 450 watts. Does that mean that i will only be able to use 450 watts of my 1200 watt cab???

1200W cab- http://www.guitarcenter.com/Behringer-Ultrabass-BB410-1200W-4x10-Bass-Cabinet-600606-i1152848.gc

450W head- http://www.guitarcenter.com/Behringer-ULTRABASS-BX4500H-Bass-Amp-Head-103311015-i1145507.gc
Cabs don't "have" watts - they don't provide any power.

A 1200 watt cab means that the cab can handle up to 1200 watts of power, power which will come from the amp head.
Actually called Mark!

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It means that it will take 1200W to blow it up. Using a 450W head means you have heaps of headroom. The speakers will be idling along not breaking a sweat.
I've often wondered what those Behringer bass amp would be like. They're pretty cheap.
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