Noisy Elmwood - could it be damaged?

[ljdsam]

Hi there. Got a problem with my Elmwood Modena 60, wondered if someone could help.

In the last couple of weeks I've noticed a hum/buzz coming from the amp, possibly from the transformer on the power amp side. It is there even on standby.

Never noticed it before, but quite aware of it now.

Also, I'm getting a lot more speaker hum than normal from my effects when I use a power supply. Previously there was only noise on the highest gain setting, now it's there with any gain.

Thinking back, the first time I noticed it was when I took the amp to a shop to try out FX power supplies. I have a nasty feeling the salesman plugged the 8ohm output from the amp into a 4 or 2 ohm speaker.

Could he have damaged the transformer, or a valve?
Would that cause this sort of problem?
I don't think the actual tone of the amp has changed, but it's certainly noisier.
Never owned a valve amp before (got this one in January) so I'm fairly clueless, so need to get my facts right before I unleash on this guys ass!!!

Thanks.

[Chuck H]

In the last couple of weeks I've noticed a hum/buzz coming from the amp, possibly from the transformer on the power amp side. It is there even on standby.

I can't find a schem for that amp. But if it's wired in a typical fasion there should be no electronic hum in standby. Examine the amp while it's in standby and see if the power transformer is vibrating.

Also, I'm getting a lot more speaker hum than normal from my effects when I use a power supply. Previously there was only noise on the highest gain setting, now it's there with any gain.

If this only happens with the effects on a power supply I would think that this isn't the fault of the amp. But rather a ground loop in the effects arrangement itself.

Thinking back, the first time I noticed it was when I took the amp to a shop to try out FX power supplies. I have a nasty feeling the salesman plugged the 8ohm output from the amp into a 4 or 2 ohm speaker.

Could he have damaged the transformer, or a valve?

It's very unlikely. Most tube amps will even run into a dead short for a time without failure. But that isn't to say that a tube couldn't have started going south coincidentally at that time.

Never owned a valve amp before (got this one in January) so I'm fairly clueless, so need to get my facts right before I unleash on this guys ass!!!

If I were you, I would take my entire rig (amp, guitar, effects and any cabinets) down to the shop and see what happens when you use it with another Modena 60. If there is a problem with tubes or ground loops the salseman should be able to help. I wouldn't unleash on anyone yet.

Chuck