@ScottRichardson I have seen tube amps/preamps with third order harmonics higher than the 2nd order even harmonics and visa versa, and many cases where the harmonics are mixed by channel as to what is predominant. @Frunse I have to take issue with your comment about speaker cables causing the differences you describe unless you are using very thin gauge wire over large distances- at least for audio. But agree with you that “everyone has his own audio heaven”