4 ohm parallel amp in to 8 ohm cabinet
- Thread starter iamtetsuo
- Start date
Securb
One of Jerry's Kids
Re: 4 ohm parallel amp in to 8 ohm cabinet
That's all good man. I was not digging in on anyone in the thread.
That's all good man. I was not digging in on anyone in the thread.
devastone
New member
Re: 4 ohm parallel amp in to 8 ohm cabinet
As has been said, with solid state, your fine as long as you stay above the minimum rating on the amp. You could run a 100 ohm cab and it wouldn't hurt the amp, probably wouldn't have much output either.
I know the original question was about SS amps, but as always, it has been brought up that it is the "opposite" with tube amps. On a tube amp, it's best to match the amp's output to the cab, but you are generally fine with a slight mismatch, like 8 ohm cab in the 16 ohm output or a 16 ohm cab into the 8 ohm output, probably best not to go too big on the mismatch though. Most people say it's safer to go lower rather than higher in tube amps but either will put stress on the amp, it just moves where the stress is placed.
Here is a good article: http://blog.hughes-and-kettner.com/ohm-cooking-101-understanding-amps-speakers-and-impedance/
Basically here's what's happening with the 2 scenarios.
When you run a load that is higher than the amp is set for, for example 16 ohm cab plugged into a 4 ohm output, it creates higher voltages in the output transformer, which could result in arcing in the transformer or possibly tube sockets. An OT is expensive to replace.
Running a lower load than the amp is set for, 4 ohm cab plugged into the 16 ohm output makes the output tubes work harder and run hotter which will substantially reduce the life of your power tubes, but, tubes are cheaper to replace than an OT or tube sockets.
And again, a slight mismatch is usually fine, in fact some companies have recommended trying it for different tones, like the fender Tonemaster head that had impedance settings of "Lo, Med, and High", but the manual also had guidelines for using the mismatch. That said, I would never run a 2 ohm load on a tube or SS amp with 4 ohms as it's lowest rating.
As has been said, with solid state, your fine as long as you stay above the minimum rating on the amp. You could run a 100 ohm cab and it wouldn't hurt the amp, probably wouldn't have much output either.
I know the original question was about SS amps, but as always, it has been brought up that it is the "opposite" with tube amps. On a tube amp, it's best to match the amp's output to the cab, but you are generally fine with a slight mismatch, like 8 ohm cab in the 16 ohm output or a 16 ohm cab into the 8 ohm output, probably best not to go too big on the mismatch though. Most people say it's safer to go lower rather than higher in tube amps but either will put stress on the amp, it just moves where the stress is placed.
Here is a good article: http://blog.hughes-and-kettner.com/ohm-cooking-101-understanding-amps-speakers-and-impedance/
Basically here's what's happening with the 2 scenarios.
When you run a load that is higher than the amp is set for, for example 16 ohm cab plugged into a 4 ohm output, it creates higher voltages in the output transformer, which could result in arcing in the transformer or possibly tube sockets. An OT is expensive to replace.
Running a lower load than the amp is set for, 4 ohm cab plugged into the 16 ohm output makes the output tubes work harder and run hotter which will substantially reduce the life of your power tubes, but, tubes are cheaper to replace than an OT or tube sockets.
And again, a slight mismatch is usually fine, in fact some companies have recommended trying it for different tones, like the fender Tonemaster head that had impedance settings of "Lo, Med, and High", but the manual also had guidelines for using the mismatch. That said, I would never run a 2 ohm load on a tube or SS amp with 4 ohms as it's lowest rating.
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