When I tune a pipe organ that has the Unda Maris and Voix Celeste I tune
them not a few Hertz, as suggested in yesterday's MMD, higher or lower
but merely a fraction of one Hertz sharp or flat.  A half or third of
one Hertz has given a satisfactory sound in all cases and is quite
effective when the added stops are drawn.

I believe that tuning "a few Hertz" sharp or flat would bring on a
dissonant sound that would be the opposite of what is desired.

Of course, I suppose, like many other things, it can be subjective.

Hal Davis