Looking for best Class D amplifier to make an active subwoofer using Rockford-Fosgate P3D4 15 inch subwoofer

That depends what you mean by "best." Crown and Behringer make some pretty cheap models with a lot of watts per dollar (and some controversy if they can really deliver those rated powers continuously or for how long). But then at http://audiosciencereview.com you can see those are not the cleanest reproducers in terms of distortion and noise...some says it doesn't matter or just swallow it due to price. Because to move to cleaner stuff like http://buckeyeamp.com costs a chunk more.

Now I'm always posting that speaker power ratings are useless nonsense, but I have to give a bit of a pass to Rockford. I worked with those folks and one day in their lab they were discussing how to get an adhesive that would keep windings on the voice coil with 2000 watts heating the coils to something nuts like 400 or 600 degrees celsius (!!!). However at least for home use I'd say the limitations are more mechanical excursion. Then you need someone to hopefully simulate that for you in your box.
  • What are the Thiele-Small etc parameters for that woofer?
  • What box are you putting it in? (Inside dimensions and dimensions of the port(s)).
 
The cult of the SINAD is splitting the wrong hairs here…at LF the driver likely produces orders of magnitude more distortion then the amp leaving the ASR argument in the circular file. Expensive clean watts or cheap very slightly less clean watts will likely deliver the same results.
 
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Hi, I am actually now thinking to go with cheapest options available in the Indian market right now.

Please suggest me which one will be the best option mentioned below. Which amplifier will drive the Rockford P3D4 15 inch subwoofer to its full potential.

Option-1: Using Two IRS2092 500W 4ohms amplifiers feeding the each 4ohm voice coil of Rockford P3D4-15, Powered using 65-0-65 torroidal transformer linear power supply.
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Option-2: Using Wuzhi ZK-3002, TPA3255 based dual 300W, 4ohm amplifier. Powered using 50-0-50 torroidal transformer linear power supply.
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ASR provides good data on how much good power an amp can produce before the distortion knee (or clipping point). Those amp modules above are not rated for 500W and 600W of clean power, but at 10 percent distortion, which is not what you want. You want to know generated maximum power before the distortion rises sharply.

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The red cursor is at the maximum clean power, which in those conditions is 48 W for a TPA3255 based amplifier, that is advertised as:
Output power: 300W*2 (4 0 load) 10% THD+N
on their web site. The measurement seems to be within spec, if you pushed it to 10% distortion. Save yourself from a lot of trouble by learning how to read power measurements. In chip amps you can see all you need when looking at the chips data sheet.

PS. In my opinion that measured amplifier, when given a good power source with high voltage and amperage, would be a good amp for subwoofer duty if total power is sufficient for intended application.
 
Note that the 3255/48V measurement in that test is at 8 ohms, so theoretically double that into 4 ohm loads (so ~120Wpc into 4 ohms) and again into 2 ohm loads (so 240Wpc into 2 ohms.).


FWIW, the quoted 1% THD ratings for the TPA3255 chip used those amps is as follows:

Total Output Power at 1%THD+N:
260-W Stereo into 4 Ω in BTL Configuration
150-W Stereo into 8 Ω in BTL Configuration
480-W Mono into 2 Ω in PBTL Configuration


It's also a 4-channel chip and it can be run in 2.1 mode. This suggests to me that the amps that were tested by ASR are configured to use only two of the four available channels, as the measured results look like those quoted for the chip being run in SE mode, but I might be wrong here.

More information here - https://www.ti.com/lit/ds/symlink/tpa3255.pdf?ts=1747952999608
 
IRS2092S amplifier boards tested in the video links shared below demonstrate that the amplifier can actually give clean output upto 300 watts before clipping.



So I am thinking to connect two IRS2092 amplifiers to dual 4Ohm voice coils of the Subwoofer. This way I can drive the sub upto 600 watts without any issue.
 
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