#1
Hey guys I was looking at the Peavey Valveking head and on the back it had an ohms select. I was wondering what this is for. I read up on it a little and this is what I understand........ It is the resistance that the sound will have through the speakers of the amp? So it has nothing to do with the wattage of the amp but rather what the speakers of the Cab can handle?
#2
I think you can put it on 16ohms so you can connect 2 8ohm cabs or have it on 8ohms for one 8ohm cab.
#3
Quote by doubtfull
I think you can put it on 16ohms so you can connect 2 8ohm cabs or have it on 8ohms for one 8ohm cab.



Ok I understand thanks
#4
Quote by doubtfull
I think you can put it on 16ohms so you can connect 2 8ohm cabs or have it on 8ohms for one 8ohm cab.


It's the other way around, 2x8ohms=4ohms... it can get confusing. Anyways the selector sets the resitance you should connect to each output. So if it is at 8ohms, you should connect one or two 8ohm cabs. You could connect a cab with higher resistance (like 16ohms) and it works (but might change the sound/volume and make your tubes last shorter) but connecting a cab with less resistance could damage your amp. also, if you didn't know, never turn the amp on without a cab connected. It will probably blow the tubes and could damage other parts of the amp.
"When the power of love overcomes the love of power, the world will know peace" - Jimi Hendrix
#5
Quote by KnarkoV
It's the other way around, 2x8ohms=4ohms... it can get confusing. Anyways the selector sets the resitance you should connect to each output. So if it is at 8ohms, you should connect one or two 8ohm cabs. You could connect a cab with higher resistance (like 16ohms) and it works (but might change the sound/volume and make your tubes last shorter) but connecting a cab with less resistance could damage your amp. also, if you didn't know, never turn the amp on without a cab connected. It will probably blow the tubes and could damage other parts of the amp.



Yes I knew that for sure but thanks for the heads up and the reply
#6
You should match your speaker's impedance with that of the amp's, notably for a tube amp (realistically, a solid state amp can actually take some level of "abuse" in regards to this matter). If you do not match the impedance, you run the risk of damaging your tube amp (the tubes, the transformer, etc).

Particularly, I don't believe it matters whether one is higher or lower than the other, it is bad if you do not match them. If the cab's impedance is greater than the amp's, the amp's output will essentially "loop" back into the amp causing damage. Similar effects are observed with the vice versa. It is a simple matter in circuits... match one circuit's impedance (your amp) with the other circuit's impedance (your speaker). If you don't, the "circuit" will not function as needed/desired (which in a tube amp means the tubes get ****ed, maybe more).

If you set your amp at "8 ohms", then each output of your amp sees an 8 ohm impedance; so match your cab as such. More than likely, that switch is simply there so you can use a greater range of cabs easily (some cabs are 8ohm, some are 16ohm, etc). All you have to do is get your cab, and select the impedance on the amp to match. Simple as that.

But to answer one of your initial questions; it should have no bearing on your amps output (in terms of wattage). This can't be said for sure, but I imagine they would design it this way.