p. 17
features overview
3
rear panel
9
Binding post outputs
Shockproof binding post speaker outputs are provided on the CPX amplifier.
For each channel, the outputs are in parallel and the speaker connection
cables can be terminated with banana plugs or stripped wires for use in the
binding post terminals, or can be connected using the Speakon outputs (9). For
sustained high-power applications, either outputs can be used; however, exer-
cise care to assure the correct speaker phasing. The red binding posts are the
signal outputs from each channel, and the black binding posts are chassis
ground. The red binding post should be connected to the positive inputs of the
associated loudspeakers. For BRIDGE mode operation, only the red binding
posts are used and the associated loudspeaker load is connected between the
two red posts.
WARNING…Regardless of what connections are used, the minimum parallel
speaker load should always be limited to 2 ohms per channel or 4 ohms
BRIDGE mode for any application. Operation at loads of 4 ohms per channel,
or 8 ohms BRIDGE mode, is more desirable for sustained operation applica-
tions because the amplifier will run much cooler at this loading. Operation
above 4 ohms per channel and even open-circuit conditions can always be
considered safe, but sustained operation at loads below 2 ohms could result in
temporary amplifier shut down due to the thermal limit circuitry.
10
Speakon outputs
CPX amplifiers utilize three 4-conductor Speakon connectors, one for each
channel and one for BRIDGE mode. Please refer to the BRIDGE MODE sec-
tion of this manual before attempting to use this mode. For each channel
Speakon, the same impedance rules apply as with the binding posts. Internally,
all the Speakons are wired in what is called the "high current" mode, with pins
1+ and 2+ in parallel, and pins 1- and 2- in parallel. For the CHANNEL A and
CHANNEL B Speakons, the respective channel output appears on pins 1+ and
2+. Pins 1- and 2- are chassis ground. For the BRIDGE Speakon, CHANNEL
A appears on pins 1+ and 2+, and CHANNEL B appears on pins 1- and 2-.
Always check the Speakon connector wiring carefully before using.
11
Mode switch
This switch is used to select STEREO or BRIDGE mode operation. It is a con-
ventional push-push type, requiring a small "tool" to activate. The IN position is
BRIDGE mode; the OUT position is STEREO mode. Exercise care when
selecting the BRIDGE mode. Accidental selection of this mode could damage
loudspeakers, particularly in bi-amped systems. Amplifier BRIDGE mode theo-
ry will be covered later in this manual.
