Correct DIY class D for subwoofers?

Hi all.

Wanting some advice if I could.

Currently have 2 X 18" BMS DIY subs in 2 sealed enclosures. Opposite corners of living room.

Currently powered by NX6000D

This is for my home theatre.

However, I'm wanting to go down the DIY Amp route for all my channels for a few reasons

More power
Light weight
Better performance

I was thinking about Purifi ET400A for the 5 channels I have and then maybe an ICE class D 2 channel for both subs.

I realise I won't have the variable gain and volume like on the NX6000 and probably not as much power outright. But these are highly efficient drivers and my thinking is I don't need more than 500W of power.

Also my AV receiver has balanced XLR outputs and Dirac live room correction so hopefully setting levels and all that will be covered there.

Is this a good idea?
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So are you thinking about diy-ing class D amps modelled after those Purifi's or ICEpowers?
Or do you mean to replace your current amps with factory Purifi/ICEpower modules?

At any rate, your requirement for more power will probably not be met as you already mentioned.
Depending on how you'd want to do it, cheaper is probably also not going to happen.
Better performance will be met with the stock Purifi's, not sure about the ICEpowers and almost surely not with designing your own.

Ok. So to clarify. I was thinking about buying a suitable case, buying the purify amp modules and Hypex power supplies and putting together my own 5 channel amp. But I'm not sure yet that I will actually save any money doing this rather than buying an off the shelf product already made

All 5 channels are currently powered by a 110W per channel power amp. (nakamichi AVP1)

Speakers are KEF reference 1 and reference 4C centre channel and LS50 meta for surround.

I know a 5 channel purify amp will be better than the nakamichi for power and quality. (Objectively measured) and more.importantly smaller and much lighter and easier to manage.

I know the ICEPower 1200 is going to have better quality and enough power for the subs (objectively measured) and also smaller than the NX6000d. And quieter. (Have replaced the fans but you still hear them a bit)

I have turned the limiter on the NX6000d quite a bit down. (Below half way) and in the toughest of movies it only just starts to clip... Yet the limiter says something silly like 40w power at 8ohms being used so anything like 600W should be fine surely.

But the ICEpower won't have dedicated gain controls / volume to level match the subs to the other speakers. Not DSP

But I have an monolith HTP1 with PEQ, delays, levels and Dirac live so don't need it really do I?

Just wanting to know that what I'm thinking of doing is the done thing and will work?...trying to make the system smaller, lighter and more minimalistic yet better quality at the same time
OK. So you dont need power. I doubt you can get better sound than what you got now without changing speakers. I dont have expertise in Class D, but some of the later Denon recievers are very high quality and then you will have all in one box. Check measurements at