The AMP MODE switch determines the in- put signal routing within the M•1200/M•1400 amplifier. Shipped from the factory, the switch is set to STEREO. This is correct for about 90% of the applications using an amp like this (hence the TYPICAL indicator near it). But you may be in the 10% bracket, requiring spe- cial input routing within the amp.
AMP MODE should be configured before operation — if you must change it during per- formance, turn down the GAIN 
controls as a precaution to protect the speakers from any inadvertent pops or thumps.
STEREO 
mode (separate left and right inputs, separate left and right outputs) is the typical setup for amplifying stereo signals.
MONO 
mode (sometimes called Dual- Mono – one mono input, two mono outputs) is for sending a mono signal to two different speaker sets, with 
controls.
BRIDGE 
mode (sometimes called
If you set the AMP MODE 
switch in MONO or
BRIDGE, use the CHAN-
NEL 1 inputs only — the
CHANNEL 2 inputs go no- where in this case.
Note: There is one exception to this rule. If you have the OUTPUT APPLICATION switched to SUBWOOFER, the inputs to Channels 1 and 2 are summed regardless of the AMP MODE setting (see 
). Also, BRIDGE 
mode re- quires special connections at the SPEAKER OUTPUTS 
.
BRIDGE
In STEREO mode, the M•1200 Power Amplifier can deliver 600 watts per side into
2 ohms. If that’s not enough, you can use two M•1200s, each in BRIDGE mode, and deliver 1200 watts per amplifier into 4 ohms. The M•1400 produces 630 watts per side into
2 ohms in STEREO and 1260 watts into 4 ohms in BRIDGE mode. Or, you can use one amp in BRIDGE mode to power a monaural system. Finally, BRIDGE mode is also popular for subwoofer applications — but please see SUBWOOFER 
for a special subwoofer surprise.
To use all the M•1200/M•1400’s power to drive one speaker cabinet using BRIDGE mode, you’ll have to do four things:
1.Turn off the power to the M•1200/M•1400.
2.Set the AMP MODE 
switch to BRIDGE.
3.Connect the positive side of the speaker cable to the Channel 1 red (+) binding post.
4.Connect the negative side of the speaker cable to the Channel 2 red (+) binding post.
5.(Okay, make that five things!) Use only the CHANNEL 1 INPUT 
(unless you’re using the SUBWOOFER OUTPUT APPLICATION).
The CHANNEL 1 GAIN control adjusts the output level of the amplifier. The CHANNEL 2 GAIN control has no effect.
Once again: Before making connections to an amp or reconfiguring an amp’s routing, turn the power off, make the changes, then turn the power back on.
OUTPUT APPLICATION
The OUTPUT APPLICATION switch should be configured before you turn on the amplifier. This switch allows you to choose between three different configurations:
LIMITER ON (TYPICAL). This is the normal configuration: 
).
LIMITER OFF is also full bandwidth audio, but without protective limiting (please see 
). SUBWOOFER mode, with 
).
LIMITER
The LIMITER is not designed to alter your sound — it’s just there to protect your speak- ers from clipping. Its effect is virtually transparent, meaning you probably won’t even notice any audible difference. We recommend that you leave it engaged (via OUTPUT APPLI- CATION 
), hence the TYPICAL label below it.
If you’re working at quiet levels all the time, or you’ve already placed a compressor/limiter in the signal path, or if you just hate compres- sion, you can leave the LIMITER out of the circuit (via OUTPUT APPLICATION 
).
The LIMITER senses when
the amp is about to be
overdriven and attenuates
the overall level just enough 
to keep the signal from clip- ping. Clipping occurs when the output voltage
no longer linearly follows the input voltage and simply stops. This causes a sine wave to
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