Specifications

10
the amplifiers are to be operated in an environment where the airflow is
restricted, such as sealed racks, cooling should be supplemented by extra
cooling fans to evacuate the heated air and aid the flow of cool air through
the amplifier.
Input Wiring
IMPORTANT
Do not directly connect pin 1 on the amplifier’s input XLR or TRS jack, to the
amplifier’s chassis, speaker ground or power ground!
NOTE: Input signal ground is not to be used as a safety ground (earth).
The input to your amplifier is a balanced 3-pin configuration and requires all
three pins to be connected. Only high quality twin-core shielded cable
should be used. When wiring for a balanced source, the connector going to
the input of your amplifier should be wired as follows:
Pin 1 = GROUND / SHIELD.
Pin 2 = HOT (In Phase - non inverting).
Pin 3 = COLD (Reverse Phase - inverting).
When wiring for an unbalanced source you must ensure that pin 3 is
connected to pin 1 (input ground), either by linking the pins in the input
connector or by the source equipment’s output wiring.
When wiring for an unbalanced source:
Pin 1 = GROUND/SHIELD
Pin 2 = HOT (in phase with the amplifier’s output),
Pin 3 = GROUND/SHIELD (joins to pin 1).
NOTE:
In-line XLR connectors often have a termination lug that connects directly to
the chassis of the connector. Do not link this lug to pin 1 at the amplifier’s
input as it will defeat the amplifier’s input grounding scheme. This lug is often
referred to as a ”drain” and is used to provide a termination to the chassis for
shielding purposes when a floating signal ground is required between the
source and destination, or when disconnecting the signal ground is required
to reduce earth loop noise, or noise induced into signal grounds from stray
magnetic fields.
Output Wiring
When wiring to your speakers, always use the largest gauge wire your
connector will accept. The longer the speaker lead, the greater the losses will
be, resulting in reduced power and less damping at the load. We
recommend using a heavy-duty, two core flex (four core flex if bi-amping) 10
to 12 gauge (2mm
2
to 2.5mm
2
or 50/0.25 or equivalent) as a minimum.