Peavey 4080, 4000 Operation Modes, Stereo Operation, Parallel Operation, Bridged Mono Operation

Operation Modes

Stereo Operation

For stereo (dual channel) operation, turn the amplifier OFF and set the mode select switches on the back panel to the out (extended) position. In this mode, both channels operate independently of each other, with their input attenuators controlling their respective levels. Thus, a signal at channel A’s input produces an amplified signal at channel A’s output, while a signal at channel B’s input produces an amplified signal at channel B’s output.

Parallel Operation

For parallel (dual-channel/single input) operation, turn the amplifier OFF and set the connector mode (CONN MODE) switch to the parallel position by depressing the switch. Both input connectors are then strapped together and drive both channels with the same input signal. Because both connectors are strapped together, either connector can be used with a patch cable to drive the input of another amplifier. Output connections are the same as in Stereo mode. Both input attenuators remain active when in Parallel mode, allowing you to set different levels for each channel. Power and other general performance specifications are the same as in Stereo mode.

Bridged Mono Operation

Both amplifier channels can be bridged together to make a very powerful single-channel monaural amplifier. Use extreme caution when operating in the bridged mode; potentially lethal voltage may be present at the output terminals. To bridge the amplifier, depress the rear panel Bridge switch to the IN position. Direct the signal to channel A’s input and connect the speakers across the hot outputs (the “+” binding posts) of channels A and B. Only channel A’s input attenuator is active while in Bridge Mono mode. Both connectors are strapped together, so either connector can be used with a patch cable to drive the input of another amplifier.

Unlike the stereo mode, in which one side of each output is at ground, both sides are hot in bridged mode. Channel A’s side is the same polarity as its input with the minimum nominal load impedance being 4 ohms (equivalent to driving both channels at 2 ohms) in bridged mode. Driving bridged loads of less than 4 ohms will activate the DDT™ circuitry (see Indicators section), resulting in a loss of power, and may also cause a thermal (overheating) overload.