View of the Hupfeld Model A Phonoliszt-Violina
and its Pneumatic Violin Actuating Mechanisms

The circular horsehair bow is driven by a large wind-motor housed (at left) in a wooden soundproofing enclosure. The small round-leather belt at the top of the shiny aluminum bow mechanism can be seen threading it way into the wind-motor's special enclosure.

All the valve chests, expression controls and other mechanisms for the playing of the violins are located in the upper portion of the casework, adjacent to the violins themselves.

Below the violin playing mechanisms, on the upper piano back frame, are a series of remote solenoid operated electrical controls, which are used to start, stop, and rewind the music rolls, or switch from one roll changer to the other. The three ceramic mercury pot switches to the left of the solenoid controls are for the motor.