@viridian
It is important to mate the amp and the load. Never forget one is building a system and all parts must work harmoniously.
Just as in the early days of AB transistor amps, some early Class D amps left much to be desired.
I do not believe that an amp with a class D output stage is representative of the spectrum of solid state amps that are available. I would try again with a traditional power amp topology. This is not a put down of class D, just a suggestion to consider an alternative.Class D is exactly representative of the amplifier spectrum. Some Class D amps are excellent.
It is important to mate the amp and the load. Never forget one is building a system and all parts must work harmoniously.
Just as in the early days of AB transistor amps, some early Class D amps left much to be desired.