Early Type 3 Pneumatic Stack
in Seeburg Coin Pianos

(Photograph courtesy of Art Reblitz)

Front view of the common type 3 “early” stack from Seeburg G #12,312, made in 1920. The front of this stack is the pouch board, secured to the valve chest with screws along the bottom edge and both ends, and with a wooden cap running the full length of the top and enclosing the vacuum chamber. The presence of this screw pattern and top cap make it easy to identify the common type 3 stack. The shorter wooden rail on the front of the pouch board has the tracker bar tubing connectors coming out the bottom (temporarily plugged for testing with short pieces of tubing and brass plugs) and has the bleeds inside, with a removable cap for cleaning.

(Photograph courtesy of Art Reblitz)

The stack from G #12,312 sitting on the bench with the pneumatics facing upward. The pneumatics in this particular stack are shorter than usual because the inside of the piano case is shallower than usual.

(Photograph courtesy of Art Reblitz)

Types 1, 2, and 3 stacks have removable wooden valve plates inside, with four valves mounted on each plate (except for the end plate when the total number of valves isn’t a multiple of four). Each valve is supported by a little hinged wooden lever with a wire valve stem pressed into the end away from its cloth or leather hinge. The valve stem has leather nuts and spacers adjusted to support the two fiber valve discs with the correct pouch spacing and valve travel. The valve discs and pouches are oriented vertically. This relatively complex design is time-consuming to restore and regulate, but its designers probably thought it would provide very fast repetition even when playing softly, compared to relatively large and heavy valves found in other brands in the early development of the player piano. In contrast, early Seeburg valves have very little mass or resistance of movement, and because they are balanced near the end of the wooden levers, gravity isn’t a factor.

(Photograph courtesy of Art Reblitz)

Front view of a later type 3 stack from Seeburg G #54,529, made in 1922. The tubing on top near the left is for the bass octave coupler (not present on an A roll piano stack), and the brass elbows in the treble are for the pipe chest tubing. This has rounded plain wooden pushrod buttons for pushing on the wippens in a piano with a stop rail, in contrast to the earlier flat buttons with action cloth that were made for the earlier piano action without a stop rail.

(Photograph courtesy of Art Reblitz)

Front view of stack in Seeburg H #54,153, made in 1922. The row of screws around the perimeter of the pouch board, and the thin wooden cap near the front of the top show that this is an early style 4-tier stack. The pneumatic and box on the front at the far left are the bypass valve for piano expression. The large elbow covered with white tape is the vacuum supply for the xylophone. The wooden box to its right with 9 tubes connected to the top is the bass octave coupler.

(Photograph courtesy of Art Reblitz)

Back view of the stack for Seeburg H #54,153. The pneumatics are of the normal length for most early Seeburg stacks, as opposed to the unusually short pneumatics on the stack from G #12,312 shown in a picture above.