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Is it a problem to plug 2 different ohmage cabs with a 100 watt head ? one 8 and one 16ohms

If it's ok ,where do I dial the selector .......4-8 or 16 ohms ??

Louis

louis wrote:Is it a problem to plug 2 different ohmage cabs with a 100 watt head ? one 8 and one 16ohms

Not the ideal situation. The resulting load would be around 6 ohms (assuming they're connected in parallel to the amp) and there would likely be a volume difference between the two cabs.

Hold off until the good Professor weighs in, but I think it's generally better to run higher, rather than lower impedance in relation to the selector setting.

Dave

Not an ideal setup... 5.333 ohms. I'd set it for 4 ohms. You'll probably lose a little volume and get a very slightly different frequency response from the amp compared to a "perfect" match.

And OldSchool's right - the eight ohm cab will get about 2/3 of the total power, so make sure it can handle it.

There's no ideal solution to that pairing, which will end up around 5.3 ohms total in parallel. I'd suggest the 4 ohm setting as that is the closest match. N.B. The 8 ohm cabinet will absorb about twice as much power as the 16 ohm.

--mark

PS. Total impedance in parallel = 1/(1/Z1 + 1/Z2) = 1/(1/8 + 1/16) = 5.33

Thank's , I understand !


If I had my DR103 (selector on 16 ohms ) with my 16ohms cab , would I solve the problem by sending a signal to a slave amp
with it's selector on 8ohms going to the 8 ohms cab ?

Louis

louis wrote: If I had my DR103 (selector on 16 ohms ) with my 16ohms cab , would I salve the problem by sending a signal to a slave amp
with it's selector on 8ohms going to the 8 ohms cab ?

Yes. In that case, both cabs are matched up with their respective power amps.

Dave

Thank's Dave ! I appreciate!

My last question would be ,

You know that I want to build or have someone buid me a Sap with KT88's ,
Could this amp have a switch in the back that would cancel the pre-amp and become a slave if I need it to?

Louis

louis wrote:Could this amp have a switch in the back that would cancel the pre-amp and become a slave if I need it to?

How about a simple "power amp in" jack?

mikhailwatt wrote: Does it have to be switched? Would a simple "power amp in" jack on the back work for you?

I guess that would be perfect!!

Louis