Dear Folks, I know some of you will think I have committed a horrible
sin but I would like to describe the results of a modification to an
Ampico A that lets it now play B rolls. First of all, let me say that
the modification was developed by Tim Westman and he built the components
to implement it.
The story starts 18 years ago when we bought a Louis XV art case Knabe
Ampico A piano. At the time we bought it, the piano was intact and it
came with a drawer, pump and stack, all removed from the piano. All the
rest of the components were missing. I had another set of Ampico A parts
at home that I had purchased with the idea of adding them to another
piano but that is another story. I figured that we could use these parts
to complete the Knabe.
Fast forward to about 2 years ago. Having made no progress on the
restoration, I engaged Tim Westman to restore the pneumatics figuring
that I could do the rest. At the time, he asked if I would like to
convert the Ampico to play B rolls. He had done this to his own piano
and it sounded great. He delivered the restored subassemblies and I
spent the last two weeks fitting everything to the piano. This was
harder than I expected as I had to fabricate most of the mounting blocks
and brackets. It is finally done and the piano sounds magnificent.
The Ampico is a very late A with the two part amplifier, all the
compensating pneumatics and other late A features. The B modification
starts with adding two holes to the tracker bar to accommodate the
sub intensity logic. The pneumatic functions include a stepper box plus
controls to OR in the sub intensity functions. It is controlled by a
switch mounted under the piano. To play A rolls, the switch is left off
and the additional logic is out of the picture and the piano responds
like a normal A Ampico. When the switch is on and a B roll is played,
the piano responds to all the B coding just like a B Ampico.
The results are stunning to say the least. The pianissimo's are the
barest touch and the fortissimo's will shake the house. Themes are
picked distinctly out while embellishments and arpeggios are delicately
laid in the background. I had previously had little interest in B rolls
as I expected to restore the piano as an A. However, the B rolls sound
so good on the Knabe now that I have started looking for more,
particularly those making use of the bass and treble sub intensity coding.
I just wanted to share this experience with the group as I am so thrilled
with the results of this project and the success of Tim's design.
Bob Conant
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