The distinguishing feature of a fugue is its contrapuntal (polyphonic) texture. This means that each of the parts is treated equally and is referred to as a "voice" even if the fugue is for instruments.
In Bach's Overture in D major the string parts are the most important and the oboes usually double the violin parts while the trumpets fill out the texture or shadow the violin parts.
Analysis of the Fugue
Exposition (bars 24b- 42)
- The principle theme of the fugue is called the subject (first heard in the 1st violins in bar 24b starting on the note A)
- This is immediately followed by the 2nd violins with the same theme but transposed down a 5th (starting on the note D). The transposed version is called the answer (bar 25)
- This is classed as a real answer as it is an exact transposition of the subject- this results in the G of the subject being answered by C natural instead of C sharp. If one or more notes had been changed to keep the answer entirely within the tonic key, the result would be called a tonal answer.
- While the 2nd violins play the answer, the 1st…