Solid state AB amp?

In that regard, its probably only running off of the driver transistors rather than the output devices.

Two speakers increase of sound pressure by 3 dB, doubling listening distance from a speaker reduce sound pressure by 6 dB. Doubling the amp power output wattage increase sound pressure 3 dB.
Its depends on how far is your listening distance and how much class a power your amp has before it switch to class b.

My amplifier is the Passion 650.  The reason for my original question was how sweet it sounds at such a nice listening volume for a jazz trio. Thought that class A could be running alone
atmasphere would you explain what that means?

I found one user review which claimed it uses what they call an "alpha Class A" circuit, but I couldn't find much more about it.

Is that the one they use in submarines?