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Audio Amplifier Power Output Cunundrum
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DW1961:
If you have a class D amplifier, such as the Texas instruments TPA3116D2, can you get any benefit from using two amp chips, unabridged, with the same power supply (given that the power supply isn't even strong enough to drive a single amp chip to full power)?

Specifics
Power Supply: 19V @ 4.7A

I'm asking if you have one amp chip and the power supply isn't even powerful enough to power the single amp chip to 100% of its specifications, could using two of the same chip create anymore power output? And, the reason I'm asking is that Chinese vendors are putting two of these chips on their "new" amps, but using the same power supply. So, they are advertising twice the power output.

I'm not understanding how they can get more peak or RMS using two chips with the same power supply, given that the power supply isn't even driving a single amp chip to 100% of its spec.

The 3116D will put out about:
 47.5 watts at 8 ohms and 24V
86 watts at 4 ohms and 24V
(page 9 from the spec sheet below)
But the amp manufacturer is only using a 19V 4.7A power supply.

Texas Instruments TPA3116D2 amp chip.
https://www.ti.com/lit/ds/symlink/tpa3116d2.pdf?ts=1596921462063&ref_url=https%253A%252F%252Fwww.ti.com%252Fproduct%252FTPA3116D2
bob91343:
Your poor grammar makes the question ambiguous.
DW1961:

--- Quote from: bob91343 on October 06, 2021, 05:51:35 pm ---Your poor grammar makes the question ambiguous.

--- End quote ---

LOL, yeah that was very unclear. Sorry about that. I've edited the question, and it was a really late night.

See above.
bob91343:
You reaction is a proper one.  I mean, how can you get 86 Watts from an amplifier that is run from a power supply only capable of 80 Watts?  Even at 100% efficiency it's not possible.

Perhaps in the fine print they specify a different supply.  How much output do they claim?

You are also correct that using two chips won't magically double the power unless they are running it way below ratings.  If they claim 10W with one chip maybe they can get 20 W with two chips.
Zero999:
It's BS. It won't deliver that much RMS power into a 4 Ohm load, with a 19V power supply, even at 100% efficiency.

P = V2/R

For a sine wave:
PRMS = PREAK/2

Therefore:
POUT = VSUPPLY2/(2R)
POUT = 192/(2*4) = 361/8 = 45.125W
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