[timind]

I have a Harman Kardon PA2200 amp which allows for bridged operation. There is a switch on the back for that purpose. I'm figuring this switch basically allows for the input signal to be sent inverted and then the inverted signal sent to one channel while the non-inverted signal is sent to the other channel.
If this is correct my question is, if this section of the amp was bypassed, could I feed a balanced input to the amp and run the amp in balance mode. This would produce the same output power as the bridged amp, correct? Of course I'd need another for stereo.
Any thoughts appreciated.

[Tone Depth]

Here's a way to do it:  http://avahifi.com/index.php?option=com_content&view=article&id=115&Itemid=238

Check out the links on the web page.

[timind]

That piece is basically what the circuit in the amp does when bridged mode is selected. What I'm wanting to do is feed a balanced signal to the amp. I may just connect a balanced signal at the input to the power amp section and see what happens. The connection point is easy to see.
The problem is the signal would not be buffered through the amp's input section. Not sure what this will do.
Good project when it's snowing outside.

[JohnR]

You'd probably want to check to be sure that the signal source is actually generating out-of-phase signals.

[BobRex]

From what I remember, the input stage doesn't change when bridging, just the driver and output stages.  As such, unless the input stage was originally designed as balanced, or you are willing to hack up the amp (or just fake it and use converters) you cannot drive a single ended amp with a balanced signal.

[JohnR]

He wants to drive the two channels in opposite phase and connect the speaker between the two hots - i.e. bridged.