Like many tricks in HiFi area,people are willing to believe expensive caps、wires、fuse、rhodium-plated sockets etc. can make sound euphonious,some
companies are to modify their crap stuff with high-priced materials and price the product at the much higher level to make people to think they are sound better.
"tone tuning",this is the word that I hear those people say most.
I often hear they say : bhse is tuned for 007 not for 009 ,carbon has too much bass ,gg and megatron are tuned for listening vocals,kgss is more "analytical" than musical...
I've built bh/carbon/gg/mega,to me,they're all great amps in the same class.