Ohm my god
March 13, 2011 12:52 PM Subscribe
The bass player in my band has this combo amp
. It has 2 internal speakers, and an external speaker jack rated for a minimum impedance of 4 ohms. If he wants to hook up an additional cabinet, what does the impedance of the extra cab need to be?
posted by anazgnos to media & arts (2 answers total)
He bought a Mark Bass 2x12 extension cab rated at 8 ohms. We plugged it in, everything sounded fine, but then we got...a smell.
He has a regular amp tech who assured him this setup would be fine but as this was the first run it made us a little squeamish.
I guess it's not clear whether that 4 ohm impedance includes the existing, internal speakers, or is just a standalone value. If his existing speakers already resist at 4 ohms, then the additional cab needs to be...what? I understand there's a formula to this, but if the info I found here
is correct (under 'Calculating Total Impedence of Different Impedance Cabinets')...then there is nothing you can add to an existing 4 ohm load that will result in anything but a fraction of 4 ohms. If anyone's familiar with hooking up a cab to this particular amp and not frying any of the components involved, that'd be great.