Circumstantial evidence indicates that the baroque bassoon was a newly invented instrument, rather than a simple modification of the old dulcian. The dulcian was not immediately supplanted, but continued to be used well into the 18th century by Bach and others; and, presumably for reasons of interchangeability, repertoire from this time is very unlikely to go beyond the smaller compass of the dulcian. The man most likely responsible for developing the true bassoon was Martin Hotteterre (1712), who may also have invented the three-piece flûte traversière (transverse flute) and the hautbois (baroque oboe). Some historians believe that sometime in the 1650s, Hotteterre conceived the bassoon in four sections (bell, bass joint, boot and wing joint), an arrangement that allowed greater accuracy in machining the bore compared to the one-piece dulcian. He also extended the compass down to B by adding two keys. An alternate view maintains Hotteterre was one of several craftsmen responsible for the development of the early bassoon. These may have included additional members of the Hotteterre family, as well as other French makers active around the same time. No original French bassoon from this period survives, but if it did, it would most likely resemble the earliest extant bassoons of Johann Christoph Denner and Richard Haka from the 1680s. Sometime around 1700, a fourth key (G♯) was added, and it was for this type of instrument that composers such as Antonio Vivaldi, Bach, and Georg Philipp Telemann wrote their demanding music. A fifth key, for the low E, was added during the first half of the 18th century. Notable makers of the 4-key and 5-key baroque bassoon include J.H. Eichentopf (), J. Poerschmann (1680–1757), Thomas Stanesby Jr. (1668–1734), G.H. Scherer (1703–1778), and Prudent Thieriot (1732–1786).
Circumstantial evidence indicates that the baroque bassoon was a newly invented instrument rather than a simple modification of the old dulcian The dulcian was not immediately supplanted but continued to be used well into the 18th century by Bach and others; and presumably for reasons of interchangeability repertoire from this time is very unlikely to go beyond the smaller compass of the dulcian The man most likely responsible for developing the true bassoon was Martin Hotteterre (1712) who may also have invented the three-piece flûte traversière (transverse flute) and the hautbois (baroque oboe) Some historians believe that sometime in the 1650s Hotteterre conceived the bassoon in four sections (bell bass joint boot and wing joint) an arrangement that allowed greater accuracy in machining the bore compared to the one-piece dulcian He also extended the compass down to B by adding two keys An alternate view maintains Hotteterre was one of several craftsmen responsible for the development of the early bassoon These may have included additional members of the Hotteterre family as well as other French makers active around the same time No original French bassoon from this period survives but if it did it would most likely resemble the earliest extant bassoons of Johann Christoph Denner and Richard Haka from the 1680s Sometime around 1700 a fourth key (G♯) was added and it was for this type of instrument that composers such as Antonio Vivaldi Bach and Georg Philipp Telemann wrote their demanding music A fifth key for the low E was added during the first half of the 18th century Notable makers of the 4-key and 5-key baroque bassoon include JH Eichentopf () J Poerschmann (1680–1757) Thomas Stanesby Jr (1668–1734) GH Scherer (1703–1778) and Prudent Thieriot (1732–1786)