trichords unisons

[Bradley M. Snook]

First a small clarification: the highest overtones are the first to fade as
the note decays. The longer you wait, the clearer your perception of the
fundamental pitch becomes (or lowest perceivable partials); the higher
partials no longer cause as much interference. In theory, if you wait until
most of the overtones have subsided, it will be much easier to set the
fundamental frequencies. But is this ultimately what shapes our perception
of a unison?  The majority of the time we probably experience unisons that
are not that long in duration. It is that initial added disturbance that our
ears are most often forced to deal with.

While I agree that setting the unisons after some partials have decayed is
an excellent method of getting a unison to sound clean, it really should be
tempered by shorter durations in order to account for the interference of
the higher partials. You have to balance both approaches to suit what you
think most often will be experienced by the listener.

The other thing to consider is that those small 'rolls' are not [as]
perceivable once you are a short distance from the piano. Using this
psychoacoustical phenomenon as an advantage, you can adjust the strings so
that they are not perfectly in-tune in order to maximize on some addition
volume and resonance: a very slight misalignment creates less destructive
interference.

Bradley M. Snook