Dear all,  I successfully re-tubed the lower action of my 1924 Marshall
and Wendell Ampico A upright a few months ago, but at that point time
and access didn't permit me to re-tube the two "bundles" of tubing
running up from below the keybed to the elbows at either side of the
upper action.  As the upper action soon needs to come out for piano
regulation, I'm preparing to replace the degrading 1980s/90s "bundles"
of tubes and am keen to get the sequence correct for the tubes either
side of the upper action.

This begs the question, was there originally a "correct" sequence for
these?  It's only a trivial point but if I'm going to the trouble of
re-tubing I'd like to get the layout authentic, especially as the
tubing is fairly inaccessible once installed.

The current sequence (running top to bottom) is very slightly illogical
in that 7B is out of its obvious place in the sequence (obviously 3T is
also out of sequence as the soft pedal pneumatic is at the bass end of
the piano):

Left (bass) end: 1B, 2B, 3B, 3T, 4B, 5B, 6B, Bass reregulator (subdued
switch), 7B, tracking device supply, uncontrolled suction supply
(larger tube).

The right (treble) end seems more logical: 1T, 2T, (gap), 4T, 5T, 6T, 7T,
8T and roll frame hole, Treble reregulator (subdued switch), Amplifier
relay (brilliant).

Can anyone confirm if this is the "correct" sequence, if such a thing
exists?  The 1923 Inspector's Reference Book, as far as I can read the
pictures, indicates a sequence significantly different from the above,
suggesting a solution which is even less logical!

I should perhaps make it clear that all the tubes currently start and
end in the right places, it's just the route in between I'd like to get
"correct" if I can.  If it is also a nice logical sequence, that would
make life even better.

Many thanks from the East Midlands of the UK,

Arthur Jones