Combining Cabs

Noctune · #1 01-01-2012, 04:31 PM

I've bought a new bass amp a Bugera BVP550, 550 watts into 4 Ohm's, which I'm running through a Peavey 4x10 8 Ohm cabinet rated at 750 watts, so I'm getting at a guess 200 to 300 watts as i said only a guess.

I'm posting because I've been offered a Behringer 4x10 Bass cabinet ( Behringer Ultrabass BB410 ) for only £50, down side is one speaker is blown so its an extra £30 for a good enough replacement.

So my question is if I paired that cab to my existing which is rated at 8 Ohms and the behringer is rated at 4 Ohms and im running a 4 Ohm head through them, how much power would I be getting out of them?

**B-string** · #2 01-01-2012, 04:38 PM

You need to know FIRST if your amp will handle a 2 ohm load to use both cabs together. Adding a 4 ohm cab to an 8 ohm cab puts the amp load under 4 ohms.

The 4 ohm cab will receive twice the amp power of the 8ohm cab.

Noctune · #3 01-01-2012, 05:14 PM

soo I take its a bad idea to combine the two then? Seeing as the 4ohm cab would be getting double the power from the amp? or would it be only the full 550 watts and the 8 ohm cab getting the 300 watts?

I read the manual for the bass head and it only mentions running at 4ohms (550 watts) and 8 ohms(300 watts).

will33 · #4 01-01-2012, 05:16 PM

Quote:

Originally Posted by Noctune

soo I take its a bad idea to combine the two then? Seeing as the 4ohm cab would be getting double the power from the amp? or would it be only the full 550 watts and the 8 ohm cab getting the 300 watts?

I read the manual for the bass head and it only mentions running at 4ohms (550 watts) and 8 ohms(300 watts).

Then don't do it, you'll burn up your amp. Only add an 8ohm cabinet, if any, to what you have now. Preferably one identical to your current cab.

**B-string** · #5 01-01-2012, 05:25 PM

Then the amp will not handle a load below 4 ohms and you can't run both cabs together. IF it could the total wattage would be higher, say 700 for example. 4 ohm cab would receive about 500 watts and the 8 ohm cab 200 watts at full output (simplified example no claims made to be absolute

).

billfitzmaurice · #6 01-01-2012, 05:50 PM

Quote:

Originally Posted by Noctune

if I paired that cab to my existing which is rated at 8 Ohms and the behringer is rated at 4 Ohms and im running a 4 Ohm head through them, how much power would I be getting out of them?

None. That's a 2.7 ohm load, which will cause the amp to shut down.
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