[quote="stereotype, post: 737813"] At the expense of screwing up the overall bass response. It is generally best to live with eigentones. They are not all-pervasive, like bass boom. ...... A tuneless boom is not the result of eigentones, which are of narrow bandwidth. Unless the acoustic is really dire and unsuitable.[/QUOTE] It depends entirely where the eigentones are - and in many uk living rooms they are clustered around 40-50hz which can really screw up bass, making it overblown and one note. Moving the speakers or listening position might reduce one of them but not all. Personally I find the effects of the room, and in some cases equipment balance far more intrusive to quality than the effect of tone control circuits. Also why assume that the studio engineers got it right? You are simply hearing their choice and there is nothing wrong with you altering it, if you then find the end result more enjoyable. Certainly if you listen to some music released today ut clearly isn't balanced for playback on a h-fi system as we know it, more likely a car system or earbuds. You can't undo that mess but you can get a more listenable result. By not having tone controls you give up all control and rely on the competence of the mastering engineer. If we were talking 1950 or 1960, perhaps 70s I might not be so concerned. Much output over the past couple of decades is all over the place!