L-Pads and Impedances

bob21

One for @ICBM and the techs..

If I have an 8 Ohm L-Pad; and a 16ohm Amp and Speaker, am I correct in thinking the combination will make bad things happen?

Just checking to see if I can use the exisiting lpad, or if I need to knock a new one up!

Thanks in advance!

ICBM

Might be a bit hard on the output valves, but otherwise not a risk to the amp. If it's a lower-powered single-ended amp it tends to matter less, they're not as impedance-sensitive. L-Pads are fairly safe as a mismatched load anyway since they're purely resistive. (Inductive loads are more risky.)

Is it both the amp and speaker that are 16-ohm, or does the amp have an 8-ohm setting too? If so, use the amp at 8 ohms into the L-Pad and then into the speaker, that's definitely OK. The amp sees the attenuator as the load not the speaker, unless the attenuator is nearly bypassed.

bob21

It's a 16 ohm amp, an AC15hw.. It's running at virtually no output anyway, I just want to shave a little off with the pad.. Sound okay?

ICBM

Yes, fine.

That's actually the best use for attenuators anyway, rather than cranking the nuts off the amp and strangling it down to bedroom level .