Why would anyone want class AB amp when class A always sounds better ?

The lowest distortion amp in existence is class AB. The problem with this amp is it doesn’t have any low-order harmonics to help mask any inadequacies in upstream gear or the recording. 

The Benchmark is as smooth or smoother than any class A amp I’ve heard...IF it’s paired with a good class A preamp. There is no point in owning a low distortion amplifier if the preamp is a weak link.

In my mind there are absolutely no reasons to own any other amp unless you either want a very colored sound or your speakers require more than 100/200 WPC, 8/4 ohm. You get an AHB2 then tailor the sound with your choice of preamp. Class A tube preamp paired with an AHB2 is that cliche “match made in heaven.”

I recently added a Gustard X26 Pro to my Benchmark HPA4 | AHB2 mono. It replaced the Benchmark DAC3B (still keeping it). The sound of my system was transformed to that of the Gustard. The HPA4 and AHB2 do not seem to add any flavor.

It’s the ultimate chameleon. What the source puts in is exactly what the AHB2 dishes out.