This isn't life or death, but I thought I'd mention it.

At the rollingball.com site, under Quasi-Equal Temperaments, they state re the Viennese Temperament: "Viennese by Johann Nepomuk Hummel Viennese Quasi-Equal 1829 An Austrian musician, known as Europe's greatest pianist, a student of Mozart,. This temperament became known as the Viennese."

At the http://www.tunelab-world.com/tempers/tempers.html, they have two separate listings.. one for the Viennese QE and one for the Johann Nepomuk Hummel QE.

The offsets for the Viennese QE are:
A 0.00
A# 0.28
B 0.00
C 0.49
C# 0.42
D -0.19
D# -0.01
E -0.39
F 0.02
F# -0.13
G 0.48
G# 0.51

But, the offsets for the Johann Nepomuk Hummel QE are:
A 0.00
A# 0.61
B 0.65
C 0.13
C# 0.41
D 0.13
D# 0.63
E 0.56
F -0.05
F# 0.12
G -0.25
G# 0.15

Danio,

The first one you mention "Viennese QE", and that set of offsets, corresponds to temperament 111 in Jorgensen's big fat red book on page 409. Jorgensen calls this "Tuning Hummel's Temperament According to the Rules of Viennese Tuners in 1829"

The second one you mention, "Johan Nepomuk Hummel QE", and the set of offsets, seems to correspond to temperament 112 in Jorgensen's big fat red book on page 411. Jorgensen call this "Hummel's Easier Bearing Plan for the 'Unpracticed Ear' in 1829"

Hope I've helped,
Chris S.

You have!

Thank you,
-Joe