Bach's first violin sonata is iconic and widely performed. The four movement sonata, although in G minor, has one flat in the key signature. This was typical in the Baroque era. Additionally, the fugue, which is the 2nd movements, was later adapted for Organ and Lute in Bach's Prelude and Fugue BWV 539 and Fugue BWV 1000. Emil Kross writes the following in his edition: In [Bach's] Adagio we find a great mass of embellishments (Runs, Turns) which must be executed with evenness and an easy grace. [Overloading with ornament] has now gone out of fashion. When studying the Adagio count very slow quavers at first and increase the tempo only after full mastery over the fingers and bow management has been obtained. To supplement the above, we add some iterpretations of violinist Guy Woodard, as mentioned in 'Analysis and Interpretation of Eighteen Violin Compositions', 1911.
Adagio - similar advice to Mr. Kross, pay close attention to time division due to the many various 'note-values in each measure', and learn the notes that form the melodic line - play this line separately to ensure it stands out when the polyphony is added. As an example, in the G minor chord appearing in the 2nd measure, the B-flat must stand out with greater bow pressure.
Fuga ('Fuga-Allegro') - 'the Fugue demands energy', mr. Woodard suggests. Where the melody is countered with double and tripple stops, one should take great care to add more bow pressure and make the melodic notes prominant. He suggests to keep in mind that this piece was first written for the organ so as to assist in the interpretation and effect.
Siciliano - What stands out is the fact that when one melody ends, another begins or continues in the third movement. As in the first few measures, after the introduction of the 7-note tune, upon its conclusion it begins again in the lower voice - which should be brought out.
Presto - Avoid playing the fourth movement too fast as it becomes difficult to 'pronounce clearly' the important notes or 'harmonic steps'. It is a common mistake to play the piece as if it were written with a 2/4 time signature; it is written in 3/8 and thus should not be played as tripplets. Each measure should audibly have three beats.