Hello, If I have an amp that has an 8 ohm and 2x 4 ohm cabinet outputs and want to use 2 cabinets that are both 8 ohm. Usually, I would need to run both 8 ohm cabs into both the 4 ohm output from the amp (Mesa).
When I program “Amp 1” as 8 ohm output and then select both the 2x 8 ohm cabs, the ZMAC auto selects 4 ohms. Is that correct or what would the correct impedance selection be in that scenario?
What impedance should be selected when running 2 cabs that are 16 ohm and 8 ohm cab out of an 8 ohm amp?
Yes, that is absolutely correct. The ZMACS will choose the correct impedance based on what you set the cabinets at. So two 8 ohm cabinets selected at the same time, the ZMACS will select the proper impedance of 4 ohms.
For your last question, you would set the impedance of the cabinets as what they are, 16 ohms. You would set the impedance of your head as 8 ohms. When you select both cabs, it will automatically choose 8 ohms. You can use the ZMACS to match the impedance of your amplifier, and cabinets.
I’ve never run into that situation running two cabs like that. If you were running two separate power amp channels with two cabs and one had a processor in it (Wet/Dry), yes, I’ve run into that. That’s super common and normally pretty easy to fix. I would check the speakers in the cabinets are wired with the correct polarity at that point.
If im running 2x 8 ohm cabs instead of just one 8ohm cab through the zmacs. Should i then switch the amp to 4ohm? Im thinking i can leave the amp on 8ohm and the impedance matching transformer handles it? Or “should” I put the amp on 4 ohm and engage the transformer bypass? Both options work correct? And it’s really upto my preference at that point?
