In the mid thirties, Wurlitzer unveiled a line of symmetrical grand pianos, or "Butterfly" grands.
 At this point in Wurlitzer history, all piano manufacturing was exclusively in DeKalb, Illinois.
 Models ranged from the Student Butterfly having 44 keys, to the 88 key Deluxe Art Deco Streamline Model 1411.

Model 1411 had many innovative patented features.
 A quartet of raised banding around the body were actually functional sound port slots that radiate all the way around the case, allowing sound to escape the cabinet with the lids closed.
 The most notable feature was the symmetrical lids that opened like butterfly wings.
 These lids open to reveal a secondary ported removable inner lid.
These lids are decoratively cut out to allow the sound to ring out via a large F hole, similar to a violin, as well as multiple radial slots along the outer edge.
 Another design innovation was the "Tone Amplifier".
 The device consists of a metal flat bar between the piano rim, running under the bass bridge to a fixed point on the soundboard, designed to bring out the tone on a smaller piano.
 A screw mechanism on top of the bridge allowed adjustment of the tonal output.

Wurlitzer made at least three different versions of the 73 key model butterfly.
  Each had variations in appointments, such as legs, lyres, and sheet music stands.
In the mid thirties, Wurlitzer unveiled a line of symmetrical grand pianos, or "Butterfly" grands.  At this point in Wurlitzer history, all piano manufacturing was exclusively in DeKalb, Illinois.  Models ranged from the Student Butterfly having 44 keys, to the 88 key Deluxe Art Deco Streamline Model 1411.
Model 1411 had many innovative patented features.  A quartet of raised banding around the body were actually functional sound port slots that radiate all the way around the case, allowing sound to escape the cabinet with the lids closed.  The most notable feature was the symmetrical lids that opened like butterfly wings.  These lids open to reveal a secondary ported removable inner lid. These lids are decoratively cut out to allow the sound to ring out via a large F hole, similar to a violin, as well as multiple radial slots along the outer edge.  Another design innovation was the "Tone Amplifier".  The device consists of a metal flat bar between the piano rim, running under the bass bridge to a fixed point on the soundboard, designed to bring out the tone on a smaller piano.  A screw mechanism on top of the bridge allowed adjustment of the tonal output.
Wurlitzer made at least three different versions of the 73 key model butterfly.   Each had variations in appointments, such as legs, lyres, and sheet music stands.
Wurlitzer