Curious find: mastering "affects one channel much more"
First: please no "you cannot hear the difference",
that is not the question. Rather: does anyone know any tools that would lead to this phenomenon, and why? Back in the day I bought a few CD collections and it so happens that I have more than one of the same release ripped. And every now and then I ran a bitcompare. Sometimes the differences are way more than you would expect from redithering, and sometimes they differ systematically across channels. Take this - figures after offset alignment, track by track on the same CD: Channel difference peaks: 0.027008 (-31.37 dBTP) 0.198303 (-14.05 dBTP)Difference always greater in the left channel. All tracks, although for one (track 7) only by the minimal amount - and up to a sizeable -76 vs -15. Channel difference peaks: 0.009918 (-40.07 dBTP) 0.013458 (-37.42 dBTP) Channel difference peaks: 0.000153 (-76.33 dBTP) 0.161407 (-15.84 dBTP) Channel difference peaks: 0.017609 (-35.09 dBTP) 0.094757 (-20.47 dBTP) Channel difference peaks: 0.005737 (-44.83 dBTP) 0.030212 (-30.40 dBTP) Channel difference peaks: 0.015350 (-36.28 dBTP) 0.167877 (-15.50 dBTP) Channel difference peaks: 0.051544 (-25.76 dBTP) 0.051575 (-25.75 dBTP) Channel difference peaks: 0.012756 (-37.89 dBTP) 0.299591 (-10.47 dBTP) Channel difference peaks: 0.034271 (-29.30 dBTP) 0.071747 (-22.88 dBTP) Channel difference peaks: 0.020752 (-33.66 dBTP) 0.100250 (-19.98 dBTP) Channel difference peaks: 0.008881 (-41.03 dBTP) 0.036041 (-28.86 dBTP) (Lazily I sanity-checked them with the whatever-it-is-worth Tau Analyzer, which differs in assessment for two tracks: One is track 7 where the difference shows up near-equal over channels, so maybe that is part of the explanation; then for the second to last track, Tau cannot assess more than one of them.) Any tool that is known to do things like this upon mastering? Uneducated guesses: Some "enhance stereo separation" filter activated but set to "minimum" which isn't completely the same as switched off? Or, deciding on dither shape by an analysis of only one channel?