I'm taking part in a discussion on another forum in which someone is contemplating connecting the L and R outputs of an amp in parallel. Both inputs of the amp would be fed by a "Y" splitter so both channels receive the same signal.

I agree with the theory that available current should be essentially doubled and improve low impedance drive capabiltiy. But, my opinion has been that it's a recipe for trouble, if not outright disaster.

Some pro amps have this capability, however they have circuits/switching that facilite this type of operation.

Is this a path to problems (or disaster) if the amps aren't designed to be operated in a parallel-mono mode?

What is done inside the amp to allow for parallel-mono operation?

What is the end result doing this to an amp without a parallel-mono mode?

I'm certainly not an expert, but paralleling two mono amplifiers at the output stage seems like you would have current sourcing issues from the load of the amplifiers upon each other as well as the speaker load. The amplifiers would have to appear as infinite impedances to one another...I'm sure it can be done with some current sharing resistor network, which would probably result in a loss of the gained current anyway (and increased output impedance)

I would certainly wear protective eyeware, hearing protection, and linesmans gloves when you turn that badboy on if you just 'twist the wires together' to see what happens!

Actually, the discussion was not about paralleling two mono amps, it was about paralleling the two channels of a stereo amp.

Seems as though the OP in the other forum has decided against it so it's sorta a moot point.

However, to satisfy my curiosity, I'd still like to hear more opinions about it.

Same thing really, a stereo amp is just two mono amps jammed into one box. Some with the ability to bridge channels, the only parallel in audio that I know for amps is simply a switch to send channel 1s input to channel 2 totally different than bridging.

In my opinion, it is a likely recipe for disaster. Connecting the outputs of two power transistors together in parallel could result in one transistor trying to pump current through the other. One or the other transistor gets blown up. I don't know the circuit used for amps which are specifically designed to be wired in parallel.

Regards,
Terry

Some "chip" amps are designed to be paralleled, but the chip manufacture has instructions on how to do it. It's more than just connecting to the speaker terminals.