Tierce en taille - example actual and historic tuning

On the way to exploring the historical sound of the Riepp organ:

00:00 Actual tuning, a1 = 420 Hz
Slightly non-equal
04:20 Historic tuning a1= 392 Hz
French tuning approach

Interesting to hear the low old French tone, smooth sound with pure harmonics, another world

The down tune was done by HW pitch re-processing, (no key shift!), so transforming the formants.
Holzhey shortened the pipes by a half-tone, to achieve a "contemporary" tuning, thus changing the formants.
The re-processing tries to approach the original sound

Registration:
HW: Princip 8, Copel 8
POS: Copel 8, Flet 4, Nazard 3, Tertz 1 1/2, Quart 2
PED: Octav 8