Hey let's not overthink this AC plug thing.
When my amplifier is wired for 240 (presently), there are 2 wires
carrying AC from the outlet to the amplifier. Be it Red/White, Red/Black
Black/White, and a Ground (Earth) Green. Depends on the particular
power cord used.
Now if the input to the amplifer is strapped for 120 v. The "hot" lead is Red
the neutral is white and the Earth is still Green.
ergo- Three wires from the amp to the wall, period.
Now, both my LK-500's have but a SPST switch in the AC input. Kinda not safe
when connected for 240 as one side is always energized. ALWAYS UNPLUG BEFORE
OPERATING ON IT!!
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