But it's not just the modules. The input and output stages matter too.
They do!
Many Class D module makers provide the option to separate the input from the rest of the amp, providing a very low impedance interface. The vendor is then responsible for making their own. This could be tubed for instance.
However, I'm not here to sell that idea. All I am here to sell you is that you can build very nice sounding monoblocks inexpensively, and if you are curious about Class D, and want to tinker, here you go.
Both ICEPower and Hypex provide it all.
The ASP modules have build in power supplies. The Hypex need you to purchase that separately.
Best,
E