Mesa NooB needs tech advice.

[WannaBoogie]

Contacted Mesa Japan : Still awaiting reply
Contacted Mesa USA ; Still awaiting reply

I have a DR 100W 3 channel head and 4x12 Recto cab on the way from the U.S.

Due to lack of research, I am now faced with a 120V/60Hz power requirement from the U.S. spec'd amp... in Japan, which is 100V/50Hz

For years, I have run U.S. fenders, and Crates off the wall jack here. But, this is my first tube amp. And, I am now beginning to understand that I may have made an error in judgement... or two.

The questions... Will it work properly? or will I damage it?

All of the "burnout" stories I have found were U.S. made amps going to Europe@240V. I've no idea what would happen if I plugged it in here... OR even if I used a 120V step up transformer... Well, same quessy applies to both scenarios I guess.

so far, I've spotted recommendations to send it to authorized service and have the power transformer replaced to the proper spec... OR use a 1st class step up transformer.

Any and all advice is greatly appreciated.

Cheers!

 

[UnderJollyRoger]

Well, the one thing I would consider is how much money you have spent for the amp and if you are willing to blow it at first power on

Voltage fluctuations are a common thing, so the amp could probably run on 100V because it buffers/transforms the supply internally, but I'm not sure about the 50/60Hz difference.

Seriously, get a transformer, unless Mesa tells you it will run fine with your voltage. I wouldn't risk trying something ...

 

[WannaBoogie]

The transformers available here will output 115V/60Hz. I cannot speak to how clean the current is though.

What concerns me is all the warnings on the Mesa site to "not do it"... and then there are those folks who say they "have done it" with no problems.

I would normally just find a Japanese dealer and get it from there. BUT, the price on a Dual Recto 100W Head averages 390,000JPY (That's $5100.00US) vs. the $1800.00US price they are asking from the US dealer. I don't see that a 100V transformer is worth an additional $3300.00. Prices here are INSANE!

What might just be the golden ticket is... that I could send it to one of the Pro-shops listed on the Japanese site, and ask them to install the new transformer...

Seem like a plan?

 

[kick6]

I, personally, don't think you'll have much trouble running it. However, the tone will be different. You'll end up getting something that sounds a little bit like the "spongey" mode when you have your amp set to the "bold" setting.

 

[WannaBoogie]

Thanks for the advice.

I just called Mercury Mag and ordered the PT with a 100V tap. This will ensure that the DR gets all the juice it deserves.
I'll have the tech install it as soon as it gets in... Then it should function famously. But, I say goodbye to the warranty straight out of the box.

The only other downside is that I am unable to wire it for a "switch"able input voltage. But, the Merc PT has 100V/120V/220V taps. So, it can pretty much go anywhere as long as a tech can do the re-wire.

This was the best solution available for now. I put a bug in Mercury's ear about input switching tranny's. Maybe they can deliver one eventually.

 

[94Tremoverb]

The transformer *is* switchable - that's why it has 100/120/220V taps. Don't go off on Mercury about something they already take care of.

The reason it won't be "switchable" (i.e. with an external switch) is that the amp does not have a selector switch, that's all. You could fit one, if you don't mind drilling a hole in the amp, but why does it matter? It only becomes an issue if you travel with your amp outside your voltage zone. In any case, external voltage selectors are a bad idea because sooner or later someone will set it to the wrong value. That is why current European regulations forbid them. (At least, hand-operable ones.) Every vintage amp I work on that has a selector, I bypass the selector exactly for this reason, because I've seen too many amps damaged by people setting them wrong.

For what its worth, making a Dual Rectifier externally voltage-switchable is slightly harder than a lot of other amps too, because it has two separate connections to the transformer for the Bold and Spongy settings. It's possible, but would need a different switch from the standard ones used for this.

 

[WannaBoogie]

The transformer *is* switchable - that's why it has 100/120/220V taps. Don't go off on Mercury about something they already take care of.

I did not "go off" on Mercury at all. I am VERY happy with their service and offerings. Read the post. I said "The only other downside is that I am unable to wire it for a "switch"able input voltage". How is that 'going off' on anyone to say that "I" am unable to do something?
And, also to the point, it was Paul at Mercury who told me that they do not have a switch ("We can not recommend a switch as this transformer is not switchable at this time")- nor could he recommend one that would do what I asked.

...but why does it matter? It only becomes an issue if you travel with your amp outside your voltage zone.

I can travel less than a mile in any direction an easily be in a 120V zone due to military bases here. But, I live and do most of my playing in the 100V zone. My environment is different from yours.

In any case, external voltage selectors are a bad idea because sooner or later someone will set it to the wrong value. That is why current European regulations forbid them. (At least, hand-operable ones.) Every vintage amp I work on that has a selector, I bypass the selector exactly for this reason, because I've seen too many amps damaged by people setting them wrong.

Point taken... But, I would still prefer to have one for my purposes. But, since "I am unable" to do the wiring. it's moot for me. But, it is still the only downside. I would be very interested in learning of any self-sensing trannys that might be available now or in the future.

For what its worth, making a Dual Rectifier externally voltage-switchable is slightly harder than a lot of other amps too, because it has two separate connections to the transformer for the Bold and Spongy settings. It's possible, but would need a different switch from the standard ones used for this.

Good information for the future. Hopefully I will be able to figure out the solution someday.
Thank you for your reply.