Speaker Cab Wattage for Running a Full Stack

[Bud]

I have a question for you about speaker cabs:

I have a 350W solid state Marshall 'Mode 4 MF350' head, and i want to run (2) 4x12 speaker cabinets; one on either side of the stage.

I downloaded the manual for the head (i got it secondhand) and when it comes to (2) speaker cabs, the manual calls for each cab to be 16ohm and at "least 235W each".
So, I have an Orange 4x12, 16ohm, 240W cab (straight face).
I have a Marshall 4x12 (slant) that is 16ohm, but 300W.
My question is: do both cabs have to be equal wattage? I know they have to have the same impedance (16), but is it okay to run a 240W cab and a 300W cab simultaneously?

thanks!
xSx

Note: this message was originally posted by Steve Karp on 3/16/12.

[Bud]

Here's your answer my friend!

Wattage ratings on cabinets generally refer to the maximum they'll handle for a duration without destroying the coil. It would be ideal to have matched cabinets but as long as they are the same ohm rating and the amp does not exceed the recommended power (watts) input, I don't see a real problem here. I'm sure some purists would object or have an electronic formula which would prohibit anything but perfection in match.

Remember that overdrive was discovered by pushing and amp/speaker combination as far as the volume control would go. The big joke always being "Turn it up to12" !! Have fun and crank it!

Note: this reply from Uncle Randy was originally posted on 3/16/12.

[Bud]

Two 16 ohm cabinets, if you are running them in parallel, equal an 8 ohm load for the amp.  So you might be okay, as far as impedance matching is concerned.

It is my understanding that running with too low of a speaker (load) impedance will draw mucho current from the amp, and many amps can't handle the rush.

You may want to test things out before using the two cabinets in a performance, because if the speakers in both cabinets are not an identical match, or if they don't have the same sensitivity ratings, you may end up with more volume coming from one cabinet than with the other.  Worse, if the impedance is too low for the amp, it'll blow.

Note: this reply from Buddy was originally posted on 3/16/12.