Here is a list of Haydn's innovative achievements that I know of:

Helped to fuse italian style with austro/german style in the early
development of the symphony,
Invented string quartet,
Invented string trio,
Invented piano trio,
Invented schertzo,
Invented classical minuet,
Developed classical sonata form,
Was the first person to stand in front of an orchestra to conduct,
Wrote the first symphony with a slow ending (Farewell),
Wrote the first symphony featuring a re-capitulation of the opening
theme at the end of the last movement (Horn signal),
Wrote the first symphonic movement with no tune (in several sturm und
drang works) proto 20c!
Developed piano sonata,
Was the first person to use multiple (3+) subjects within symphonic
sonata form.
Developed the art of bringing opera acts to a climax.

Am I right?
Am I wrong?
Have I missed out anything?
Has anyone invented more in the history of music?

Bob Draper
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