changing from 220v to 120v

it really depends on how a specific unit is built and whether it is internally configured with proper power transformers and circuitry to handle different input voltages - some are easy to do, made for quick-shift... others not so much

so i would lean on the manufacturer to advise on the wisdom of the input voltage swap

I woulds never buy a 220v amp to be converted get 110v only it could be a problem.

James Tanner, owner of Bryston, recommended not buying amps built for a different country. I am going to heed his advice.  I'm also worried the warranty might not transfer.

thanks for all the responses. 

jumpers needs to be resolderedhttps://ibb.co/RC4NntF

+builder3, call Bryston.  While your at it, make sure with Bryston that there are no warranty issues if you do it yourself.

Bryston probably knows.

I know nothing about the internals of Bryston, but it's often just spades on a terminal block.  Takes a phillips head screwdriver and voila. :)

Do you know whether Bryston builds their amps for easy conversion?

If the dealer is doing it, without sending it back to Bryston, then it’s easy.
"Could" even be an internal switch, or soldered bridging pads
Cheers George

Shouldn't be a problem. Cheers,
Spencer

Thanks for the response.  Do you know whether Bryston builds their amps for easy conversion?

Depending on the gear, yes. With linear power supplies we often see transformers that are manufactured as dual voltage units. These transformers use two primary coils, and depending on whether the primaries are connected in series or in parallel to each other they work with 220 or 110.

It’s a common cost-saving technique.

Best,

Erik