Allen Organs and Stretch

[Glenn Grafton]

-Bob Scott wrote:
>  I seem to recall measuring the pitches of an Allen digital organ a number
>of years ago. I was surprised to find that it had some designed-in stretch.
>Does anyone know how they decide how much stretch a digital organ
>should have?  They obviously don't need to worry about inharmonicity.
>Perhaps they are trying to make the Allen correspond a little more with
>pianos for when they are played together?
>
>   -Bob Scott
>   -Ann Arbor, Michigan

We're the Allen Organ dealer for the Phila./S. Jersey area. I'm not too
involved with the organs but as I understand it, all the tuning paramaters
of the organ are able to be set to whatever the designers want. This
includes the tuning on one keyboard with one stop down, the differences in
tuning with different stops and different manuals on the organ. In other
words they can design the organ to have the ideal tuning that a pipe organ
would have and it stays permanantly.

I recall a pipe organ builder & friend who stopped in the store, he also
taught a course on organ in one of the colleges in Phila. We're standing by
the grand pianos with Allens smallest organ behind us. He was explaining
how the problem with the digital organs is that the tuning was locked in
because it was a computer. As he was saying this I reached over, turned on
the organ & started playing a few intervals on one manual, added a stop,
etc. He stopped and said, "how is that happening?"

We had a church call this week to get their piano tuned, "to the Allen
Digital Computer Organ." The lady said that a previous tuner said that the
organ was sharp, compared to the piano. I said that that wasn't the case
and a tune can just tune the piano to A-440 and they'll match fine. A
previous post here said accurately that the 8' Principle on the great is
tuned to A440. Other stops may be sharp or flat for ensemble. This is quite
different from the scenerio I've encountered with many pipe organs under
service contracts where the organ is basically tuned where it's at and
we're faced with the prospect of tuning a brand new piano a 1/4 step flat
to match the organ.

Glenn Grafton
Grafton Piano & Organ Co.
Souderton PA