> ... using a reproducing piano will let us illustrate it without any
> performance variation on a real instrument.

This idea strikes me as somewhat strange.  I'm not sure what would be
on a piano roll labelled "Well-tempered Clavier," insofar as the Bach
work is actually 96 individual pieces of music, totaling about 3 hours
of music (48 preludes and 48 fugues, two each in all major and minor
keys).

I assume the Ampico roll (if it is indeed from the Bach work and not
some other work named after it) would only be one or two of these
pieces.  A recording of WTC on paper would require many, many rolls!
And the point would be to hear how all the keys sound, particularly
in any unequal tuning system.  Using just one or two individual works
would come nowhere near demonstrating the potential of the tunings.

As has been suggested, there are recordings of some or all of
"Well-tempered Clavier," available on recordings and on the web,
using a variety of temperaments.  Brad Lehman's own website has some.

If one can play, he or she can also find a harpsichord and experiment
with equal and various unequal temperaments at will.  (And, I should
point out that the distinction is somewhat less clear on the
comparatively dull sounding piano, as compared to the harpsichord.)

David C. Kelzenberg
Iowa City, Iowa, USA