Whirlwind ISO 1 Line Level Isolation Box Single Channel Line Level Isolation Transformer

The ISO 1 is a single channel line level isolation box. Put it across a feed that is picking up hum and buzz in a broadcast or live sound tie line and the transformer breaks the path the noise was travelling on.

It also converts an unbalanced line to balanced, which is the right move before a long cable run. A ground lift switch disconnects the input ground from the output when the isolation alone is not enough.