Originally Posted by Bill Fitzmaurice
Look at the specs, these for instance:
Note how the bridged minimum impedance load is twice that of the per channel minimum impedance load.
What you're saying would be true if the two channels were parallel bridged, an option that used to be seen on some amps. But the vast majority of amps today use series bridging, and just like placing a pair of batteries in series voltage doubles, current delivery remains the same.
All the capacitors are used the same way regardless if the amp is bridged or not.
When you bridge the amp one channel signal is inverted and the voltage swing of the two channels sum. It's as simple as that. Voltage swing capability is doubled, current capability is the same as a single channel.
Ohms Law bears it out quite clearly. When the amp is run at 4 ohms bridged it's like running 2 ohms in stereo.
In the amp being discussed...
2 ch operation @ 2 ohms is 2000WPC (4000W total output) per the spec, which is the result of (approx.) 63V and 32A current (per channel).
When the amp is bridged with 4 ohm load, the spec is 4000W. This is the result of (approx.) 126V and 32A current.
As you see, current isn't increased at all per channel in this bridged mode situation but you get doubling of the voltage swing resulting in double the power.Edited by whoaru99 - 11/6/13 at 11:20am