(Photograph courtesy of Art Reblitz.)

Empress Electric Solo Expression Twin Tracker (a.k.a. Model L). The upper interior contains the simple roll mechanism. The unit on the left end of the shelf has a slide valve pushed left or right by a pneumatic at either end. The pneumatics are actuated by forward and reverse holes in the music roll. The slide valve in turn controls a shift pneumatic on the back of the spoolbox, which lowers the drive shaft to play forward, or lifts it to play in reverse. The slide valve also controls two sets of cutout pouches in a box below the spoolbox shelf, turning one half of the tracker bar on and the other half off. There is no high-speed rewind mechanism, nor is there the usual waiting for the roll to rewind as in most other pianos that play spooled rolls. The bass hammer rail pneumatic is visible just above the hammer rail on the left side of the case.

(Photograph courtesy of Art Reblitz.)

Bottom interior of the Solo Expression Twin Tracker piano (a.k.a. Model L), with the expression and control mechanisms mounted under the left end of the keybed. The larger pneumatic in front is the main expression regulator. Of the two smaller pneumatics to its right, the front one is a two-stage accordion pneumatic. The regulator collapses until it hits a lever mounted on the accordion pneumatic and the piano plays softly. When either or both stages of the accordion pneumatic collapse, the lever opens the regulator pneumatic farther, providing a total of four expression levels (0, 1, 2, or 1+2). The back pneumatic is for accent (see the tracker scale text on the main Empress Electric page). We welcome additional details from anyone who owns a piano of this model with its original mechanisms.

Photograph courtesy of Art Reblitz.)

Another view of the lower interior of the Solo Expression Twin Tracker piano (a.k.a. Model L) showing the two hose connections at the hinge end of the intensity accordion pneumatic. The coin accumulator (just above the open coin box) is similar to those used in Nelson-Wiggen pianos.