firemanj92, thanks much for chiming-in. Nice to see an amp fit under the dash.
Did you remove the factory amp also? Looks to be fairly straight-forward:
http://www.toyota-4runner.org/3rd-g...xperience-pulling-amp-limited.html#post974407
Do you recall what gauge wire you ran to & from it?
Since I already have a pair of those Polk DB651s, which seem like a wise choice, and I'd need just a couple more, I'd like to go that route. So, I'm compiling a list of compact amps for this application.
I'm getting some indications that the JL Audio HX280/4 might be discontinued, but even if so, still available, as firemanj92 revealed.
JL Audio HX280/4 - 50 watts RMS x 4
8-11/16"W x 1-13/16"H x 3-1/8"D
https://www.crutchfield.com/S-Va7Hnh0oqWS/p_136HX2804/JL-Audio-HX280-4.html
Clarion XC2410 - 50 watts RMS x 4
8"W x 1-11/16"H x 3-1/4"D
Alpine KTP-445U Power Pack - 45 watts RMS x 4
7-7/8"W x 1-1/2"H x 2-9/16"D
https://www.crutchfield.com/S-ahlJ2edOGEm/p_500KTP445U/Alpine-KTP-445U-Power-Pack.html
All three are about the same dimensions, and likely to fit under the dash They all deliver 45-50 watts RMS to each of four speakers, at 4 ohms. They are all Class D amps. Price range for all three... Now that I look further, it seems that the JL Audio HX280/4 is not for sale. If so, it's $200+. The price range for the other two (Clarion and Alpine) is $100 to $115.
Power output, slight edge to the Clarion (50w vs 45w RMS)
THD for each is the same at 1%
SNR for the Alpine is 82 dB, better than 70 dB for the Clarion
Any other considerations?