Interior of the
Wurlitzer Style 33-A
Mandolin PianOrchestra
Philipps Pianella Model 33
(Hanulec/Kehoe collection, circa 1998)

Interior view of left side of the Wurlitzer style 33A Mandolin Pianorchestra.
(Photograph courtesy of Joe Hanulec/Walter Kehoe)

Left Side Interior showing the mitered wood Violoncello pipes, the tambourine and its reiterating action, and the end of the xylophone are visible in the upper section.

The bass end of the piano and one end of the main valve chest (or stack) are easily seen in the lower section's access opening.

View of the bass drum and associated mechanisms from the left side.
(Photograph courtesy of Joe Hanulec/Walter Kehoe)

View looking through the upper left side access door, up between the back of the xylophone resonator box and the wooden pipework. The two smaller beaters astride the larger central bass drum beater are for kettle drum effects. The ride cymbal (fastened to the upper left top rim of the bass drum) is operated by a sturdy wire striker fastened to the center bass drum beater assembly.

Interior view of the right side of the style 33A Mandolin PianOrchestra.
(Photograph courtesy of Joe Hanulec/Walter Kehoe)

In this right side interior view the bass drum can be seen mounted on the top side of the drum support shelf, which also supports the triangle and castanet actions. The snare drum and its reiterating action hang inverted below the shelf.

Visible at the top edge of the lower access opening is the orchestra bell assembly, which is partially obscured by the case. The bell strikers hang downward, with the metal bell-bars and resonator box at the bottom side of the assembly.

Frontal view showing a portion of the register unit, xylophone and pipework.
(Photograph courtesy of Joe Hanulec/Walter Kehoe)

A portion of the register unit is visible at the lower right in this right front interior view. The register unit is a rather complicated device containing both primary and secondary (lever or rocker type) valves. The small wooden dowels sticking up at the front of the unit are the guide stem portion of the very sensitive primary valves.

The treble end of the reiterating xylophone is visible at the lower left, with the three ranks of wooden pipework rising up in the rear. The large pneumatic motor fastened to the end of the xylophone operates the swell shutters, which are mounted in the roof of the PianOrchestra.

Frontal view showing a portion of the feeder pumps and crank drive mechanism.
(Photograph courtesy of Joe Hanulec/Walter Kehoe)

In this lower right front view, the large cast-iron, round-leather belted, crankshaft pulley is belted to the electric motor. This, pulley in turn drives the pump crankshaft via roller chain reduction gears, providing a powerful, slow, and steady speed for the bellows type feeder pump.

The feeder pump, fastened to the floor of the PianOrchestra, serves a dual purpose, and provides both vacuum (front set of bellows) and wind-pressure (rear set of bellows, which are not visible).

Frontal view showing the electric motor and a portion of the vacuum reservoir.
(Photograph courtesy of Joe Hanulec/Walter Kehoe)

This lower left frontal view shows the electric motor in the bottom, with the vacuum reservoir located directly behind it. To the immediate right of the vacuum reservoir is the regulating spill valve for wind-pressure, held closed by two flat steel springs.

On the shelf above the motor the bass end of the main valve chest or stack can be seen. The small wooden dowels on the pneumatic stack (just below the piano action) push up against the piano action whippens, causing a note to sound.

At the middle left is a standard Wurlitzer coin-trip accumulator, which credits and debits up to twenty coins. Notice the absence of a coin chute, as this and most large PianOrchestras were generally operated by remote wall boxes.