Brunette Girl With The Sax

Sax's patent expired in 1866; thereafter numerous saxophonists and instrument manufacturers implemented their own improvements to the design and keywork. The first substantial modification was by a French manufacturer who extended the bell slightly and added an extra key to extend the range downwards by one semitone to B♭. It is suspected that Sax himself may have attempted this modification. This extension was adopted into almost all modern designs.
Sax's original keywork, which was based on the Triebert system 3 oboe for the left hand and the Boehm clarinet for the right, was very simplistic and made playing some legato passages and wide intervals extremely difficult to finger, so numerous developers added extra keys and alternate fingerings to make chromatic playing less difficult. While the early saxophone had two separate octave vents to assist in the playing of the upper registers just as modern instruments do, players of Sax's original design had to operate these via two separate octave keys operated by the left thumb. A substantial advancement in saxophone keywork was the development of a method by which both tone holes are operated by a single octave key by the left thumb which is now universal on all modern saxophones. One of the most radical, however temporary, revisions of saxophone keywork was made in the 1950s by M. Houvenaghel of Paris, who completely redeveloped the mechanics of the system to allow a number of notes (C♯, B, A, G, F and E♭) to be flattened by a semitone simply by lowering the right middle finger. This enables a chromatic scale to be played over two octaves simply by playing the diatonic scale combined with alternately raising and lowering this one digit. However, this keywork never gained much popularity, and is no longer in use.