Amp ohm mismatch

[Jay.lingelbach]

I got a a new amp. Didn't check the rating.  It's a 16ohm 4 watt head. And an 8 ohm cab rated for 30w. Will this damage anything?


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[WormBoy]

I got a a new amp. Didn't check the rating.  It's a 16ohm 4 watt head. And an 8 ohm cab rated for 30w. Will this damage anything?

If it is a tube amp, I wouldn't do it: you might well damage something and it probably won't sound like it should. If it is a solid-state amp, I would try it and see how it sounds.

Edit: on reading up a bit more, I would not do it for SS amps either (the other way around would be fine for a SS amp). There is a quite a bit of different ideas on this, apparently. If you have a tube amp, it *might* be fine, but I personally would not take the risk if its a new or beloved one.

[Jay.lingelbach]

I got a a new amp. Didn't check the rating.  It's a 16ohm 4 watt head. And an 8 ohm cab rated for 30w. Will this damage anything?

If it is a tube amp, I wouldn't do it: you might well damage something and it probably won't sound like it should. If it is a solid-state amp, I would try it and see how it sounds.

Good to know. Thanks!


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[WormBoy]

But note my edit in my first post ...

[SirEgno]

The rule is different for tube amp (or with output transformer in general) or solid state (or OTL - output transformer less):

1.Tube/OT - impedante must be the same for head and cabinet;
2.SS/OTL - the cabinet impedance must be same or higher than the head impedance.

[WormBoy]

The rule is different for tube amp (or with output transformer in general) or solid state (or OTL - output transformer less):

1.Tube/OT - impedante must be the same for head and cabinet;
2.SS/OTL - the cabinet impedance must be same or higher than the head impedance.

That would be the safe thing to do. The manual for my solid state Quilter head says (after advising which speaker output to use for the best match): "The amplifier will not be bothered by impedance mismatches, so if the tone sounds OK, go for it!" So it will probably also depend on the amp design. But my guess is that the TS has a tube amp (I think there won't be that many 4 Watt SS guitar amps out there).

[thesmokingman]

re: tube amps, it really depends on the technical specifications of the output transformer, the tubes, and how the amp was designed (bias, class, etc) ... if you've got an overengineered amp that isn't running on the ragged edge of exploding in class a-b you can run a reasonable impedance mismatch probably forever and you'd not really notice ... if you're running the tubes hot on an undersized output transformer in class a your mileage may greatly vary

[Aentons]

What amp is it? Sometimes there is a 8/16 ohm switch. Did you check for that? What cab, and how many speakers? If there are two then you might be able to change the wiring for a better match

[skyled]

For tube amps it is safe to run a speaker cab with higher ohms than the amp's recommended ohm output. Usually it's ok to run a cab with one step lower in ohms than the amp, as long as the volume is kept lower. I would say go for it, but don't crank it.