xxxsoundxxx
. . . He was actually commenting /surprised on how the high string note groups are slightly out of tune just like a real piano. I guess it is hard to get the high strings perfect and keep them there and that attributes to the "real" sound true pianos has. Cool.
As I understand it, piano tuners deliberately tune the upper octaves progressively sharper relative to absolute pitch. This is to allow for the fact that the harmonics produced when a piano string is struck do not have a simple arithmetic relationship to the fundamental.
So for example if the note A (440Hz) is played, on most instruments the 2nd harmonic would be exactly 800Hz, the third harmonic would be 1200Hz, etc. Piano strings produce harmonics which are very slightly sharper (a function of the way the bridge deflects slightly when the string is struck then quickly returns to its original position).
If the notes of the upper octaves were tuned to their 'correct' frequencies, they would sound flat in comparison to the harmonics produced by the lower strings. Sharpening them slightly compensates for this. One reason why early attempts at synthesized piano tones were not convincing.
For those who were interested :-)