Cabinet Matching

[metalmm785]

Hello to everybody,
I tried to look this up and didn't come up with a solid answer. Basically, i wanted to know if it's safe to hookup my mesa 2x12 alongside my mark's internal speaker (speaker is a c90 8ohms) at the same time into both of the 4ohm hookups available in the combo. Since 2x 8 ohms would be 4?.... I apologize if this has been covered already but i wanted to make sure i don't damage my amp. I've been runing the 2x12 to the 8ohm hookup since i bought it, but curiosity got ahold of me.
Thanks a bunch for any input,
Mike

 

[stokes]

So long as the ext cab is also 8ohms that is the optimum way to hook it up.

 

[metalmm785]

Yes, my mesa 2x12 is a 8 ohm cab. Thanks for sharing.