Date: 1926. Owned by Jim Sparks
The Wonderphone family consists of the 80J and 81J which have three valves, and the 82J/83J (pictured here) which have four valves.
What Conn said in 1926:
The Wonderphone Model BBb Bass built with detachable curved bell, in either three- or four-valve types, has been built for many years by C.G. Conn Ltd., and has served most satisfactorily in concert bands and orchestras owing to its rich, full and mellow tone. This model is of the same bore and pitch as the regular Conn "Monster" BBb Bass, and is in all respects similar to that instrument, with the added feature of the adjustable bell, which enables the performer to throw the tone in any direction desired. When used in concert, the tone is thrown toward the audience rather than upward, and the advantage of this can be readily appreciated.
This model is used by some artists in their phonograph work, who prefer it to the CC Phonograph Model. The Wonderphone is also used in some dance orchestras where the Sousaphone Grand is not in evidence.
Many of our most capable artists use this model in preference to the regular upright basses, and nothing but the highest endorsement has been given to the Wonderphone by those who have played it.