My impression is that the different ranks of a harpsichord
are normally tuned in unison with each other, often either in
some flavor of meantone or in an irregular tuning that gave
a satisfactory compromise between thirds and fifths in all
the keys the player expected to use. The different ranks
would be used for dynamic or coloristic effects, just as on
the organ.
> Harps, historically, were almost certainly tuned to a specific key,
> as the only referent for tuning would be using the instrument's
> harmonics to tune with, which yields just intonation by default.
Medieval harpists quite likely tuned by pure fifths,
producing a Pythagorean intonation (perfect fifths,
ghastly thirds). Renaissance and early baroque harps
were mostly likely tuned in some sort of meantone
(lovely thirds, narrow fifths), just like keyboards.
Bill McJohn
billmc@microsoft