Using a 110V to 220V step up transformer


I have an opportunity to buy an SET tube amp, however it is 220 volt. Any issues with using a step up transformer? Hum, high noise floor, etc? 

jboyd302

No problem at all. Get one rated for the current draw/amperage of the SET amp - which can't be much!

It will work fine. However, you need to get a good quality one.

I have a 240V tube amp by Ayon. Recognize that european current is set up differently than US. they have 2 wires, a hot wire and a neutral wire (plus a ground). In the US we have 3 wires, 2 hot and one neurtral (plus a ground). Both hot wires are 120V to neutral but 240 V (ac) hot to hot. But your amp PROBABLY won’t know the difference.

The Ayon has a phase indicator light on the back to tell you if your outlet is wired backwards and you are (in europe) plugged hot to ground and ground to hot. When plugged into US 240, the light is on, but the amp performs flawlessly.

Getting back to transformers. Most (but not all) transformers will take US 120 V and step it up to US style 240V. I did find one brand, marketed as a conversion for european appliances, that output european style 240 V. But many that are sold as conversion for European appliances, output US style 240V.

Then I installed a 240 Circuit and quit using a transformer.

But the cheap transformers all hum Tripp lite is a good brand. Also, oversize the transformer by a factor of 5. Most SETs actually pull less than 100W but get a 500 or 1000W transformer (for the same reason we put in good quality power cables, etc) expect to spend over $500.

Finally, I used 240V, you said 220V, some say 230V. It is all the same. Just different terminology (except Japan).

And the frequency difference is inconsequential.

Jerry