Measuring Class D output

[The Dude]

Possibly the reason for the bridged amps is that they only need to make one module for either stereo or mono purposes.

[glebert]

Possibly the reason for the bridged amps is that they only need to make one module for either stereo or mono purposes.

For stereo amps absolutely. I have two mono class D amps that are bridged though, just to double the voltage swing.

[Enzo]

The parts is a tiny part of the cost of the amp, and the boards are made by machine, so labor is not any different. Bridged outputs gets twice the power from a power supply.

[glebert]

Doubling the voltage multiplies power by four, doesn't it?

[J M Fahey]

Both are right
Doubling voltage quadruples power ... into the same impedance.

So bridging , say, 2 x 100W@4 ohm amps would give you a mono 400W@4 ohm amp.

BUT now each 100W amp is asked to deliver 200W on its own ... either it overheats and blows up or power supply simply canīt feed it whatīs needed.

SO you must double load impedance ... which "lowers" power output into what they can handle.

So a bridged 2 x 100W@4 ohm amp becomes a mono 1 x 200W@8 ohm one.

So doubled swing, plus doubled load impedance becomes twice the individual channel power output.