This is interesting! Why dissonances would become more dissonant as pitch is lowered? Is it an opinion or a physical fact?
Speaking as a piano tuner, I can say it's a physical fact on a piano. Much less so on a harpsichord, and undoubtedly much less so on a vihuela also. Piano strings are so thick, and under the pressure that they can only sustain because of the metal frame, that the overtones do not come in at exact harmonic intervals, they are a little higher because the string isn't flexible enough to bet at exact halves or thirds or fourths. With low notes the mud produced by those out-of-tune overtones is in your hearing range. With high notes it's out of your hearing range.
Judy Judith Conrad, Clavichordist -- http://home.mindspring.com/~judithconrad/index.html To get on or off this list see list information at http://www.cs.dartmouth.edu/~wbc/lute-admin/index.html
