Subwoofer amp recommendations

Hi, I’d like to build up a subwoofer for my hifi, possibly home theatre. About 500W appears plenty. I like making stuff and figure a completed class D board with crossover and level control that I can add a power supply to might be a good option. I think I’ve found most of the plate amps and they look good but I don’t mind doing a bit of extra diy to save a few dollars or possibly get a better result for the same money?

Any suggestions?
Thanks FauxFrench. There look to be a few IRS2092S based options out there.

Anyone have recent experience with any specific IRS2092S examples?

Also, the boards I found didn’t appear to have a break out board with crossover and level pots. I think I could add the level control with a pot on the input side but I’d need some help with an adjustable low pass filter.
I can not advise you to use a DIYS analog low pass for such a construction.

In nearly any situation, a sub needs a low pass, phase corrrection and some kind of boost and mode reduction. To build that analog is nonsense in times of cheap DSP´s.
Have a look at cheap DSP, like from Dayton, easy to use, simple software, many options. You only need to use one channel, even when the smallest versions com with two in/ four out. If you tried it once, you will never come back to analog. With sub frequency, don´t worry about any sound quality, 16 /24 bit, HD or whatever. The basic versions will do.