What cab ohm to use ??

8

 

4 Ohms. Wire the cabs parallel for 2 Ohms or series for 8 Ohms.

An 8 Ohm cab parallel to a 4 Ohm cab would create 2.67 Ohms, and an 8 Ohm cab in series with a 4 Ohm cab would create 12 Ohms.

 

The M9 will do 2 ohms so it (2.67ohms) will be fine and (maybe you can correct me on this) if you were to get a 4 ohm 2-10 and run it with a 4 ohm 4-10, the 2-10 would be running pretty hard and trying to keep up with twice as many speakers. Plus, with the speaker outputs on the M9 being in parallel you wouldn't have to "wire" them, rather just plug one into each jack.

 

I think that 8 Ohms is the best answer.

By having the impedance of the 2x10 twice that of the 4x10, it will get 1/2 the power of the 4x10, so each driver will see the same power. Safer. If they BOTH were 4 Ohms, each cabinet gets the same power, so the 2x10 drivers are taking twice the power each of the 4x10 drivers.

Going to another 4 Ohm cabinet will draw the most power from the amp, since it can handle loads below 4 Ohms, but you won't hear the difference.

 

8. That way all 6 of your 10s will get the same juice.

 

Definitely 8 for that application. And check for similar sensitivity for both cabs.

 

Check for -3dB sensitivity for the 210

 

+1 go with an 8 ohm 210, and also, don't forget to flip the switch on the back of the M9 to 2 ohms. Very important.

 

Yep - 8 ohm 210 ... OR ... a (second) 4 ohm 410

 

Yes, 8 Ohms for the 210''-cab, so every single of the six speakers will see the same power. This would be a nice solution.