"bridge mode"

[Pbassred]

Apart from "the switch on the back" (lol). what is happening when a stereo amplifier is put into mono "bridge mode"? Is it simply joining the 2 reds and 2 blacks together? Or making it run in push-pull?


Ok, you can shoot me now........

[Jan Dupont]

I wont shoot you...
If you don't ask, you don't learn

Bridging an amplifier means that it goes push-pull...

The input from one channel is feed in normaly polarity to one channel of the amplifier, while the same signal in opposite poalrity (inverted) are dfeed to the other channel.
In this way, you will get twice the voltage sving on the output.

Just remenber to connect your speaker between the + speaker outputs of the left and right channel....

[Pbassred]

so, a zero gain op amp to flip polarity at one input. and the neg outs are left unconnected?

[EchoWars]

Originally posted by Pbassred
so, a zero gain op amp to flip polarity at one input. and the neg outs are left unconnected?

Well, not all use an opamp to flip the polarity, but that's one way.

Once bridged, the load is no longer referenced to ground (or the chassis anyway), so yeah, the '-' terminals are unused. It is floating. The output stage of each channel sees half the normal load, so with an 8 ohm load each channel 'sees' a 4 ohm load. For this reason a little care must be taken deciding if a load is suitable to be used on a bridged amplifier.