Recommended Power Converter for a USA Amp .

musicalstash

Hi ,

can anyone recommend a safe/ noiseless stepdown  transformer ( cheaper the better )  so I can use a USA Valve Amplifier  in the UK . 

thanks in advance
s

DJH83004

Can you let us know what amp you have so we can work out the power consumption and hence make a recommendation.     Gve us a clue 

musicalstash

Sorry. ..it's a ampeg m15 20watt. 

ICBM

Something like this will do.

https://www.maplin.co.uk/p/240v-to-110v-300w-voltage-converter-vr05f

Be aware that the power rating you need is *not* 20W - that's the rated (clean) audio output power of the amp. The power draw will be much higher. I had a look at the schematic and the fuse value is given as 2A on a 120V supply, so the amp must draw less than 240W - so at worst, you need a 300W transformer.

In fact, it's likely to be less than that - my guess from the output power, number of valves etc would actually be somewhere between 100W and 200W, so a 200W transformer would almost certainly be safe, if you can find one cheaper than that - but there's no disadvantage to going bigger than you need, other than size and cost.

Kebabkid

I use what ICBM recommended for my one on a Divided by 13 and no issues 

ecc83

"Noiseless" ? Why? If noise could be a problem, silent recording perhaps, you could be bothered..

Such transformers are not designed for High Fidelity equipment and so can buzz a bit! If that is a problem you will need to get it a good distance from the amp. No bad thing in a "Studio" anyway since the things chuck out an horrendous hum field!

Dave.

nick79

I use a Goldsource st500 with my Mesa, works fine. 

algroves1

Sorry to hijack - can anybody recommend a step-up to power an Amp B15R?

Cheers

Al

DJH83004

As IC says a 200watt transformer would be more than sufficient, giving you a factor of 10 input to output, and less weight to cart around.

ICBM

DJH83004 said:

As IC says a 200watt transformer would be more than sufficient, giving you a factor of 10 input to output, and less weight to cart around.

I had a look for 200W transformers, but the ones I could easily find were not a lot smaller than the Maplin 300W one, and actually more expensive!

musicalstash

Thanks for taking the time out to answer my enquiry.  To be honest I did not realise that the converters would be so bulky .  Thanks again 

ICBM

musicalstash said:

Thanks for taking the time out to answer my enquiry.  To be honest I did not realise that the converters would be so bulky .  Thanks again 

If you get a tech to meter the amp can can be sure the power draw isn't over 100W at flat-out volume - which is just possible - you could get a much smaller transformer.

https://www.maplin.co.uk/p/maplin-230v-to-110v-100w-voltage-converter-rs59p

Don't be tempted to buy the other sort of 'voltage converter' by the way - these are small and light, but only suitable for a limited number of applications, mostly resistive heating devices like hairdryers, and not for an amp. That's why (in my opinion) the proper units should always be referred to as a *transformer*, not a 'converter'. I know Maplin and many others do mix them up.