I've had quite a lot of experience with Triphonolas (Triphonolae?) and
completely rebuilt two to date.  One was a fine Bluethner Aliquot grand
in a plain mahogany case, the other a better-sounding (to my mind)
Roenisch grand in a mahogany "pie-crust" case.

From my experience with a good many Hupfeld instruments, Bluethners
seem to have been rather unwilling to modify their grands sufficiently
to make the installation really elegant: there always seem to be some
big tubes visible underneath, and some Bluethner Phonolas look quite
pregnant! The Bluethner I rebuilt had a curious hybrid installation with
fan expression pneumatics and a few Bakelite unit valves, and a pump in
a bench.  It was mid to late 20s, and seemed somewhat experimental.

The earlier Roenisch, like all I have encountered, being one of
Hupfeld's house instruments, had a completely integrated system.
Virtually all the windways from the top action were concealed in the
key bed, and the expression units were all quickly demountable,
connected by face gaskets and wing nuts.  Very neat.  The pump was in a
tall matching cabinet with space for rolls.  This piano had push-button
controls in the left top cover, and automatic switching to Triphonola
operation, activated by the two soft-rail check-unlock perforations
found at the beginning of Animatic T rolls.  Its expression system was
like that shown in the standard Triphonola service manual (in German)
of which I have a photocopy.  It was very well designed and made, and
operated faultlessly when rebuilt.

The Triphonola is a full reproducing system.  It uses two expression
control pneumatics each for Theme and Accompaniment working in
differential mode, whose opening and closing speeds are determined by
bleeds.  Any can also be instantly opened or closed by an 'Accelerator'
signal.  Their function is complex and beautiful to behold.  Both
pneumatics may rest open (pp), one closed one open (low mf), the other
open the other closed (high mf), or both closed (ff).  The set opening
and closing speeds of each one are the same, but different from its
pair, and they can also be 'strobed', so very finely graded changes in
dynamic are possible as well as instant resetting to the reference
points and departure to a known dynamic between notes.  The
accelerators and reference points are constantly used, particularly on
the Theme side.

This system achieves the same result as the Duo-Art while not using
binary steps and with only 6 dynamic ports.  The rolls must have been
fiendishly difficult to code, but do play all 88 notes.  Most of the
early recordings were surely translated from those for the Dea.  The
Triphonola is indeed very excellent -- probably the second best
pneumatic reproducing system ever invented: now, from experience, I
believe the Duo-Art is the most natural and convincing of all the
reproducers when working correctly.

Triphonola rolls are certainly scarce, especially in the UK, and
re-cuts seem very unlikely.  As with the Duo-Art, some 'recordings' are
much better than others.  Triphonolas are complicated and not easy to
rebuild, especially the later ones with Bakelite or aluminium unit
stack valves.  When they are good they are very, very good, and most
allow pedalling of non-expression Themodist/Solodant rolls with superb
control like all normal Solophonolas.  (The Duophonola is
electric-only.)

More on (Tri)phonolas here on the Digest or direct from me if anyone
wishes.

Patrick Handscombe
Wivenhoe, Essex, UK.