@darkknight8586 I believe Krell KSA 150 and 250 operate in Class A and deliver plenty of power. There are some other Krell models such as sustained plateau biased models also operate in pure Class A. There is one KSA 150 available for $2,500 if you are interested. KSA 150 burn 300W when at idle! Class A efficiency is very low around 10-15% tops. For this reason, I purchased little brother in this series KST 100, but Class AB biased. Imaging, depth, spacing around instruments are outstanding.