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Neal
October 10th, 2009, 04:44 PM
I have a Fender bassman 70 head, that is rated 4 ohms speaker output. Would it do harm plugging it into a 16 ohm cab?

markb
October 10th, 2009, 04:56 PM
Yes. What speakers are in the cab? If it's a 2 or 4 speaker cab you might be able to rewire it for 4 ohms.

http://www.colomar.com/Shavano/4x12wiring.html

jim p
October 11th, 2009, 04:49 AM
The rule of thumb I have seen is half or twice the impedance is OK but four times is probably too much. At half or twice you will be getting approx half the output power from the amplifier. Having half will give you better bass response. Tube amps are the opposite of solid state a short is not lethal while open circuit can kill it. On a solid state amp a short can fry the output while it could care less if it is open circuit.

Neal
October 11th, 2009, 06:33 AM
I think that that answers my question. I was planning on using the cab of the PV Classic 30, which is 16 Ohms.

I wanted to use the head for lead, but the matching 8 Ohn cab, has a single 15" speaker. It sounds a little too heavy for lead.

Thanks for the responses:AOK