Running a Marshall at 220 volts

[riker4208]

Hey guys, I was trying out a marshall the other day from a cool older guy that hadn't played in a long while. Older JCM 800 set on 220 volts on the back dial instead of the 120. Well the wiring in my home is 120 as is everyone else I know. Maybe his garage is wired 220? Anyway can you hurt an amp by running it at 220 and feeding it 120? The amp was cutting out here and there.

[Mr. SD-1]

Originally Posted by riker4208

can you hurt an amp by running it at 220 and feeding it 120?

YES

[SatelliteAmps]

No! Setting an amp voltage selector to 220v, and plugging it into a 120v wall will not damage anything. The amp won't work, because it will only be getting half the voltage. The selector might be hard wired inside the amp.

[JMItones]

Some amps will power up but function at a lower power - usually with bad sound. But it is possible it would come on and function at half power.

[Griz]

'Scuse me for askin' a dumb question, but if it has a voltage selector switch on the back, as the OP seems to indicate, why not just select 120v (after verifying the local wall outlet voltage)?

Do this with the amp shut down, obviously.

[SatelliteAmps]

Originally Posted by Griz

'Scuse me for askin' a dumb question, but if it has a voltage selector switch on the back, as the OP seems to indicate, why not just select 120v (after verifying the local wall outlet voltage)?

Do this with the amp shut down, obviously.

I thought the question was more of a "did this cause any damage" kind of question, rather than a "should I change the voltage selector"

[riker4208]

I'm interested in buying the amp and was curious if it would have even worked if there was a mismatch. The amp seemed fine but hadn't been fired up in a while and had the scratchy pot syndrome where it would cut out when you turned the knobs. I later started to wonder if the power was the issue. I think the guy just had his garage wired 220.

[Reeltarded]

Uhh..... not to a 110 plug. Hey, change the voltage selector and find a 110 socket.

A Marshall can operate at half voltage, I do it all the time, and it sounds great! It should still be moving enough air to have to scream over it. Wired 220 and you have a proper plug for it? Here? In America? Not likely. Something is up.

[SatelliteAmps]

Originally Posted by riker4208

I'm interested in buying the amp and was curious if it would have even worked if there was a mismatch. The amp seemed fine but hadn't been fired up in a while and had the scratchy pot syndrome where it would cut out when you turned the knobs. I later started to wonder if the power was the issue. I think the guy just had his garage wired 220.

Worked? Yes, it would have made sound, but it wouldn't have sounded good, or loud. It is possible the guy has his garage wired for 240v. A lot of washers & dryers are wired for that voltage. Can't you just call the guy and ask?

Originally Posted by Reeltarded

Uhh..... not to a 110 plug. Hey, change the voltage selector and find a 110 socket.

A Marshall can operate at half voltage, I do it all the time, and it sounds great! It should still be moving enough air to have to scream over it. Wired 220 and you have a proper plug for it? Here? In America? Not likely. Something is up.

You run a Marshall at 60v? That is something I do at my shop when troubleshooting, but there is little audible sound coming out at that voltage. The heaters are barely warm enough to do anything. There is a little noise, but I wouldn't say it sounds great.

[Reeltarded]

Yeah, 65ish. Still can't hear the TV even a little. I like the sound. It's easy on my old man ears.

I have a couple amps here that still make a little snot at 42v. I don't honestly know what I have at the wall here, but I think we are over volt by 10%. a 100wt bulb hurts my eyes and leaves purple spots for 15 minutes. I am just reading off a variac that I have metered on a known 120 supply.