Fiske's operation was considered to be the best in its time.Conn operated it as a company subsidiary, and in this way he achieved his objectives.In 1898, upon the suggestion of Sousa, Conn developed the first commercially successful bell-up sousaphone ("the rain-catcher").
Conn patented his rubber-rimmed mouthpiece in 1875 (with patents to follow through 1877) described as "an elastic face [i.e., a rubber rim] where the mouthpiece comes in contact with the lips, the object being to prevent fatigue and injury to the lips." About this time Conn met Eugene Victor Baptiste Dupont (b. Conn's partnership with Dupont was dissolved by March 1879, but he was successful in attracting skilled craftsmen from Europe to his factory, and in this manner he expanded his operation so that by 1905, Conn had the world's largest musical instrument factory producing a full line of wind instruments, strings, percussion, and a portable organ. Armstrong, Joseph Jones, and Emory Foster to manufacture a twin-horn disc phonograph called the 'Double-Bell Wonder' that was produced in two iterations briefly in early 1898 before a lawsuit by the Berliner Gramophone Company caused production to cease.He was also the first commander of the Elkhart Commandery of the Knights Templar. After the war, Conn returned to Elkhart and established a grocery and baking business. Conn's entrance into the musical instrument manufacturing business was the result of a split lip.Colonel Conn also served as Lieutenant Colonel of the 2nd Regiment of Uniform Rank, Knights of Pythias, and was re-elected many times as Commander of the local G. There are three existing stories of how this occurred, but the popularly accepted version is that Del Crampton slugged him in the mouth outside a saloon where both of them had been drinking.The company's product line now centered around the 'Wonder' cornet, but in 1885 Conn began importing French clarinets and flutes. Lefebvre, a well known soloist with both Patrick Gilmore's and John Philip Sousa's bands.Conn started production of the first American-made saxophone in 1888, after being shown an Adolphe Sax saxophone by his employee Ferdinand August Buescher and agreeing to produce copies of it. Conn's instruments were endorsed by several leading band directors, including Sousa.When his enlistment expired he returned to Elkhart, but re-enlisted on 12 December 1863 at Niles, Michigan in Company G, 1st Michigan Sharpshooters.At the age of nineteen on 8 August 1863 he was elevated to the rank of Captain.Brick-red 'Wonder' records were also pressed for the 'Double-Bell Wonder' talking machine by the Scranton Button Works from pirated Berliner masters.Fewer than fifty 'Double-Bell Wonders' were produced of both iterations combined.The company was sold in 1980 then again in 1985, reorganized under the parent corporation United Musical Instruments (UMI) in 1986. Conn survives as a brand of musical instruments manufactured by Conn-Selmer. With the outbreak of the American Civil War he enlisted in the army on at the age of seventeen, despite his parents' protests.The assets of UMI were bought by Steinway Musical Instruments in 2000 and in January 2003 were merged with other Steinway properties into a subsidiary called Conn-Selmer. On 14 June 1861 he became a private in Company B, 15th Regiment Indiana Infantry, and shortly afterwards was assigned to a regimental band.