Starting in 1930, C. G. Conn Ltd. began production of a cornet that would create a legacy lasting all the way up to 2007: the "Director".
The first-ever Conn "Director": the 26A.
Image from The Conn Loyalist: http://www.xs4all.nl/~cderksen/Conn26A1930image.html - originally from http://www.vintagecornets.com/
The specific design being patented later in 1931, the Conn "Director" 26A cornet was produced to satisfy a demand for a classic-sounding cornet. This cornet was originally a professional model before World War II, but the "Director" horns made in the 1950s all the way up to the last "Director" trumpets available from Conn-Selmer in 2007 were student models. Here is a small showcase of the various horns and the impact they made...
The original "Director" 26A (there were no "Director" trumpets, trombones, or French horns yet) was produced from 1930 to 1941, when it was discontinued. In 1954, the basic design and layout of the "Director" was recycled to form a new student cornet, the 14A. The trumpet counterpart, the 14B (the letter A was used for cornet models, B for trumpet) was introduced as well. There also was a Coprion (100% pure copper, formed by electrolysis) version of both produced, the 18A/B. In 1960, both models were updated to create the 15A/B and 17A/B, with brass and Coprion bells, respectively. Both models were kept until 1971.
The Conn "Director" 15A: possibly the most common Conn cornet available today.
Image from The Conn Loyalist: http://www.xs4all.nl/~cderksen/Conn15A1968image.html
In 1971, the brass-belled student horn became the Conn "Director" 19A/B (later becoming the 16A/B in 1973), and the Coprion counterpart became the 21A/B. These horns were produced in Japan by Yamaha, and were designed by Schilke. Note that the Coprion bell may not have been true Coprion, but ordinary spun copper (the bells were spun polished, and weren't as smoothly finished as "classic" Elkhart Coprion bells). In 1980, the 16A/B became the 18A/B, first being distinguished by different braces, then different valves and waterkeys plus a new bell engraving. These later "Director" horns (starting with the 1981 18A/B) are known for having "Director" on the bell and the model number on the leadpipe:
When United Musical Instruments was formed in 1985 to absorb Conn, the 18A/B was discontinued, but the "Director" name appeared attached to the 22B trumpet all the way up in 2007! This "Director" model was touted as being "Director, B♭ easy to hold, easy to play!". The only Conn horn to carry the "Director" name on itself was the Taiwanese 27B trumpet, discontinued not long before the 22B. By the end of 2007, the 22B model was replaced by the 23B student trumpet, which does not carry the "Director" name. The Conn 14D single French horn carries the "Director" name today, however ("Director Single Horn in F...").