I don’t buy the "gas guzzler" A/B vs. "green" class D arguments for the latter. Kilowatt hours are cheap and relatively clean until you pile up a WHOLE lot of ’em. With typical audiophile usage patterns, and the fact that we’re a VERY small segment of the population, there’s no significant ecological impact here.
The extreme case would be a 100+ Watts pure Class A amp user, who leaves amps on 24/7, switching to a class D amp. Then yes, you’re going from a $1,000+ yearly power bill to like 100 bucks. But that’s an outlier. With more sane usage patterns -- e.g. a class A/B tube amp that you turn on/off as needed -- the difference is close to negligible. And as far as ecological impact, class D probably makes things worse overall, due to the fact that audiophiles ship ’em over, decide they don’t like the sound, and then ship ’em right off again.
The extreme case would be a 100+ Watts pure Class A amp user, who leaves amps on 24/7, switching to a class D amp. Then yes, you’re going from a $1,000+ yearly power bill to like 100 bucks. But that’s an outlier. With more sane usage patterns -- e.g. a class A/B tube amp that you turn on/off as needed -- the difference is close to negligible. And as far as ecological impact, class D probably makes things worse overall, due to the fact that audiophiles ship ’em over, decide they don’t like the sound, and then ship ’em right off again.