Why don't you just do a voltage conversion on the amp?Ask and find out if it is easy to do?Some just involve moving wires,flicking switches ect.E-mail HK to see what is involved.I have a cal audio DAC which was a simple job,so was a Bel canto power amp,it was just pulling out the fuse holder and turning it around,and a Conrad Johnson pre, which was a transformer re-wire after Conrad Johnson service department sent me instructions of how to change it,very easy.I would try this approach first,before adding another transformer to the chain.