Accustic Arts Power 1 - operates in Class A?

IIUC, by definition all class A/B amplifiers are class A at very low wattage. Some makers will bias their amp so that it is in class A even at moderately loud volume levels. In that way the amp is only operating A/B at very high volumes.

Thank you. I think based on the wattage consumption not moving at until I reach high volumes that the Accustic Arts Power 1 must be biased to Class A at least for the first few watts. Does anyone know for sure?

On one hand crossover distortions are reduced at slightly higher level when amp stays longer in A class biasing (higher bias) but at the same time gm doubling distortion at higher levels are increased. Measurements made by Douglas Self, Bob Cordel and many others show the lowest distortions at particular bias (optimal bias). Overbiasing is not the trade between quality and power dissipation but it will increase distortion. Mentioned gm doubling is change in gain of amplifier's output stage between class A (two transistors working) and class AB (one transistor working). Perhaps there are ways to minimize effect of gm doubling (trans-conductance doubling) but increasing bias in amplifiers not designed for that might lead to increased distortions.