Connecting The Speakers; Chassis Ground - Madrigal Audio Mark Levinson ?20.6 Operating Manual

Connecting the speakers

When the speaker cables are complete, connect the + (positive or
red) output post of the Nº20.6 to the + (positive or red) input terminal
of the appropriate loudspeaker. Connect the – (negative or black)
output post of the Nº20.6 to the – (negative or black) input terminal of
the appropriate loudspeaker.

Chassis ground

A black binding post is provided on the rear panel of the Nº20.6 for
connection to chassis ground. This connector is for use where the
chassis of two or more components must be interconnected to
reduce hum.
PRECAUTION NEVER use this binding post as a loudspeaker connection.
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