@best-groove Those russian toroidal step-down transformers are cheap:
Here you can find 1600w version, i use the same, but 1000w.
They are all available for japanese (100v) or for american (110v).
Stepdown auto-transformers from 220/140 to 100 (or to 110v) depends on the version.
New models designed for audio:
"Unlike the auto-transformer, the transformer provides galvanic isolation of the load circuit from the mains. The transformer acts as a filter for impulsive noise arising in the primary network."
you can read here about 100w version and here about 400w version.
Here you can find 1600w version, i use the same, but 1000w.
They are all available for japanese (100v) or for american (110v).
Stepdown auto-transformers from 220/140 to 100 (or to 110v) depends on the version.
New models designed for audio:
"Unlike the auto-transformer, the transformer provides galvanic isolation of the load circuit from the mains. The transformer acts as a filter for impulsive noise arising in the primary network."
you can read here about 100w version and here about 400w version.