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level attenuators are active, allowing you to set

different levels for each channel.

Never connect either output terminal to ground

or in parallel.

3. Bridged mono

To bridge the amplifier, depress the Link switch (6)

and Phase reverse switch (5). Both channels are then

driven by a single signal at either input. You can

use any remaining input connectors for linking etc.

Do not use the remaining XLR and TRS as input

jacks simultaneously for mixing or other purposes.

To obtain an output, connect the speaker leads to pin

+1 on channel A Speakon to speaker positive

terminal and pin +1 on channel B Speakon to

speaker negative terminal . Do not connect either

of the -1 (negative) pins of the Speakons. Do not

connect speakers to channel A or B in the normal

manner in bridge mode, as this can cause serious

damage.

Figure 10. Bridge mono connection

The recommended minimum nominal impedance

for bridged mono is 4 ohms (equivalent to driving

both channels at 2 ohms).

Driving bridged loads of less than 4 ohms may cause

a thermal overload.

Both level attenuators must be at the same position.

We recommend you to put them in the 0 dB (full)

position.

4. Stereo reverse

This mode is similar to the Tandem mono mode.

Apart from depressing the Link switch , you also

depress the Phase reverse switch, like in the Bridge

mono. Channel B is now phase reversed. To

compensate for that, connect pin +1 on channel B

Speakon to speaker negative terminal and pin -1

on channel B to speaker positive terminal.

Figure 11. Stereo reverse mode

Channel A output is connected as in the normal

stereo mode. By having channel A and B operating

in opposite polarity, the energy storage in the

power supply is more efficient. This means that the

amplifier can deliver up to 10% more power than in

tandem mono mode. This is significant for signals

below 100 Hz (sub bass etc.).

Operation

1. Operation precautions

• Make sure that the power switch is off before

making any input or output connections or

operating the switches on rear panel. See pages

4-5 about installation.

• Make sure that the AC mains is correct and the

same as that is printed on the rear panel of the

amplifier. See pages 4-5 , about operating

voltage and power consumption.

• Make sure that the switches on the rear panel

for operation modes ,clip limiters, etc. are in

the correct position. See pages 6-7, about

operation modes and page 8 about clip limiters.

• It is always a good idea to turn down the gain

controls during power up, to prevent speaker

damage, if there is a high signal level at the

input.

2. Input attenuators

The two input level attenuators on the front

panel, alter the signal level for their respective

amplifier channel in all modes. They are calibrated in

dB to help setting up active loudspeaker systems or

cutting down unwanted noise from the input signal.

In bridged mode, both controls must be in the same

position, so that the speaker load will be shared

equally between the channels.

3. Gain switch

The gain switch located on rear panel is for

changing the input sensitivity of the amplifier. This

can be handy when using low or high nominal input

signals e.g. most professional mixing consoles

operate at a nominal level of +4dBu therefore use the

29dB position (depressed switch), to give you plenty

of fader movement. On the other hand, for a disco

mixer that operates at a nominal level of 0dBu, use

the upper position setting, which has a sensitivity of

0 dB for full power in 4 ohms.

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