[Antonmb]

REL is quite specific that the ground wire should not be connected on a fully balanced amp. I have two RELs using high level connections: on the D’Agostino Momentum, which is balanced, the ground wire floats/is unconnected. I have it capped with a wire nut. On my Luxman SQ-N100, it sounds fine with the ground wire connected to a negative post, but there is sound leakage to the speakers when headphones are connected, so I have it connected to the phono ground lug instead.

Following is from the manual for the Carbon Special, but they’re all the same:

“For differential (i.e. fully balanced) amplifiers using one REL, simply use the standard connecting scheme with the exception of NOT connecting the black wire to a negative speaker terminal. Instead, it should first be allowed to “float” or hang down without connection to ANY terminal. Should hum occur using this method, please try connecting to an unused RCA connector on the rear of a preamp or amplifier.”