I am the owner of a Knabe/Autopiano player piano, built in 1912.  The
piano is equipped with "Flexotone", a device of unknown operation and
purpose.

It consists of three keyslip-mounted buttons with designation-plate
inscribed only "FLEXOTONE".  Each button is attached to a lever.
The three levers are attached at the rear to rods which extend upward
through the keybed and keys, which have holes drilled through them.

The linkage after that, as well as whatever it connected to is gone.
The linkage was all situated directly in front of the spool-box
transmission.  I've seen one other piano (not a Knabe/Autopiano) so
equipped, but it had been similarly disconnected.

As both of the pianos which I have seen so equipped were in the San
Francisco Bay Area, it could have been a local or regional after-market
product.  As both of the pianos so equipped also have had this device
disconnected, it may have been of questionable value, either musically
or mechanically.

As you have probably by now guessed, my questions are:

1. What was "Flexotone"?
2. What did it do?
3. How did it do it?
4. Has anyone else ever seen one of these?

Regards,

Bob Loesch