So far as the zh270 going up in price 10 fold, i'm not too sure about that Lewm. I wasn't aware that they were ever 2500.00 when they were first introduced but if that was the case I can't imagine Berning doing anything but breaking even if one is to consider that the amps took him 30 hours to assemble. The wiring for the impedance converter alone must be done manually and I can only imagine how tedious that task alone is. Yes indeed, at 2.5K it must be one of the greatest values ever in audio. at its final price with all the modifications I believe it listed at 5.5K
There were some substantial improvements, at least in my experience with several of the mods that improved the amp's performance no less than a wiring change and a few input caps along with some other lesser changes including cryoed outputs. The total net gain was significant. While I have done a direct AB to a Joule VZN80 in my system many years back the Joule clearly was harmonically richer with greater density where as the Berning was somewhat leaner. This was before I performed any of the mods and tweeks including much experimentation with vibration isolation. Sure would love to do an AB with the Atma-sphere in my set-up, I have always been curious all these years. I can imagine your system, great choices!
There were some substantial improvements, at least in my experience with several of the mods that improved the amp's performance no less than a wiring change and a few input caps along with some other lesser changes including cryoed outputs. The total net gain was significant. While I have done a direct AB to a Joule VZN80 in my system many years back the Joule clearly was harmonically richer with greater density where as the Berning was somewhat leaner. This was before I performed any of the mods and tweeks including much experimentation with vibration isolation. Sure would love to do an AB with the Atma-sphere in my set-up, I have always been curious all these years. I can imagine your system, great choices!