Bach Invention 4 trill question

[koitako]

Hello, i was recently checking out the Busoni edition of the Bach Inventions and something strange came out:

https://imgur.com/3LWTxZf


The ossia says that i should play the trill in 16ths notes... is that right? i've been playing the trills as fast as possible(something like 32ths)

any help is appreciated

[nystul]

Ossia is an alternative suggestion.  This is another option from Busoni on how to play the ornament.  Note that the first ossia there is not a simple trill at all, and both of them are actually in triplet 16th notes.

Busoni's standard realization of the trill is shown in the first measure of the trill... 32nd notes starting on the primary note.