Hello All,  I had to double look at this one.  Is Les dropping the
organ scale by one whole tone or just moving everything down one to
the left on the white notes only?  I had to draw a quick sketch of
a keyboard to check if I could make sense of it and to be sure I was
in the right area, so here goes.

If we move one whole tone then low E becomes D, but F becomes D-sharp
and F-sharp becomes E, G becomes F and so on -- simple transposition.
If the organ scale is non-chromatic you still have to apply the same
rules: you can't tune between the cracks as the music will sound daft,
that is, of course, unless you want to tune a Mean Tone or Werkmeister
1, 2 or 3 temperament, etc.

Also, beware of tuning reeds away from their designated pitch.  They
are voiced to sound at a given pitch and the curl of the reed tongue
is optimum for its tuning position and wind pressure.  Tuning reed
pipes as much as a tone up or down will cause them to go unstable,
and even moving them a half a tone will cause a wobble.

Hope I got this right; no doubt someone will write if I haven't.

Paul Camps