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Bridging two identical amplifiers to increase the rms output power Answered

Hi, i was wondering  if i can bridge two identical amplifiers, to drive a 4ohms 400w-rms dvc subwoofer, the second problem is what about the power supply, i don't think i can use one 24volt car battery for the two amps so can i use two separate car battery, below is the amp i want to bridge.

JBL GX-A3011SI 1200W Class D Mono Car Subwoofer Amplifier.

Product Info:

Low Distortion Class AB Design
Active Low Pass Filter
Noise Rejecting Differential Inputs
Filter Range 30Hz to 320 Hz
Peak Power Output  1200 W
4-Ohm Power Output  200 W RMS x 1, <1% THD+N
2-Ohm Power Output  300 W RMS x 1, <1% THD+N
Design Low Distortion Class AB
Input Variable Line Level and Speaker Level
Signal to Noise Ratio  93dB

since the output rms @4-ohms is "200 W RMS" so bridging two of this amps will give me a 400w-rms.

Thank you.


You should still be able to bridge with a single supply. You need to make a separate amplifier to split the signal before the main amp, by inverting the input to one side.

"You should still be able to bridge with a single supply" you meant i can power with a 12v car battery, thank you.

Yes, two amps, one battery, but I have to find the full data sheet for the amplifer to confirm it. The amp might be bridged already, in whcih case you are out of luck.

oh!! i thought a mono amp is not bridged that's why i choose a mono amp
anyways i can't find the datasheet for this amp on the net BTW i haven't
purchased the amp yet as you know i want to be 100% sure if i can
bridge the amps or not cos i have to buy two of those amps, maybe i can
go for a 2ch/4ch bridgeable amp because they are not bridge by default
anyways this is very very much needed info thank you so very good brother for your kind help and time, appreciated.

It depends on how it works internally. A bridged amp can still be mono, but a stereo amp may be bridgeable, its about the internal circuitry.

well I thought this way might be bit easier(cheaper(: but humm(: I think it will be better just getting a 400w-RMS mono block amp"better save then sorry(:" but it doesn't comes cheap nu(: mono block amps costs more than stereo amps yes(why is that) anyways I have to think(: thanks much good brother, appreciated... Regards...

Thank you good brother but i don't quite understood, what do you meant by...

need to make a separate amplifier to split the signal before the main
amp" and "by inverting the input to one side" apologizes as you know i
am new to electronics, anyways do i need another amplifier for the
"split signal before the main amp, if you can point me to some tut it will
be of great help to me.

Thank you

You should be able to just use a pair of y-RCA cables t split the input to both amps.
To get your desired power levels both amps must operate in 2-CH bridge mode.
Or for just two spears in mono mode.

Thank you good brother that solved my another problem.