More power for better sound at low volumes?

"If not, what is the secret to better low volume sound?"

A good pure class A ss amp or a good SET amp would be half the equation. The other half would be the right speaker. Many multiple way speakers do not sound coherent until they are turned up a bit.

Sometime in your journey you should try a SET mated with an appropriate speaker. It's may not be the end of the road for you but I think will be "near" the end.

Jlance369, but it doesn't take the overuse of uppercase letters to perceive your point any louder or cleaner.

Upper case letters are clearer at low volume.

I've had giant horn loaded speakers and small bookshelf speakers...at the same low volume level they both are low in volume, and things aren't as audible because they just aren't. That's just the way it is, and one must learn to accept it. Or not.

Switching from Paradigm Studio 100 speakers to Avalon Acoustics Eidolon speakers with no change in electronics created a huge improvement in low level listening.

Initially, it seemed like the Eidolons provided better low volume bass. After further listening it became obvious the Eidolons were simply far better at providing a cohesiveness throughout the entire bandwidth at any volume compared to the Paradigms.

An obvious price difference for sure. The lesson learned was the overall importance in the roll of a quality speaker system over quality electronics.

Considering you're using panel speakers I would strongly suggest auditioning the Saunders Sound Magtech amplifier using their free trial offer even though your current electronics are outstanding. There is another post here were an owner of Dartzeel electronics recently switched to JRDG and found them superior.