An extract on #fenerbaheaktr
The first of the regular canons, this is a canon at the unison: the follower begins on the same note as the leader, a bar later. As with all canons of the Goldberg Variations (except the 27th variation, canon at the ninth), there is a supporting bass line. The time signature of 12/8 and the many sets of triplets suggest a kind of a simple dance.
This is the first of the hand-crossing, two-part variations. It is in 34 time. A rapid melodic line written predominantly in sixteenth notes is accompanied by another melody with longer note values, which features very wide leaps:
The Italian type of hand-crossing such as is frequently found in the sonatas of Scarlatti is employed here, with one hand constantly moving back and forth between high and low registers while the other hand stays in the middle of the keyboard, playing the fast passages.
Variation 10 is a four-voice fughetta, with a four-bar subject heavily decorated with ornaments and somewhat reminiscent of the opening aria's melody.
The exposition takes up the whole first section of this variation (pictured). First the subject is stated in the bass, starting on the G below middle C. The answer (in the tenor) enters in bar 5, but it's a tonal answer, so some of the intervals are altered. The soprano voice enters in bar 9, but only keeps the first two bars of the subject intact, changing the rest. The final entry occurs in the alto in bar 13. There is no regular counter-subject in this fugue.
The second section develops using the same thematic material with slight changes. It resembles a counter-exposition: the voices enter one by one, all begin by stating the subject (sometimes a bit altered, like in the first section). The section begins with the subject heard once again, in the soprano voice, accompanied by an active bass line, making the bass part the only exception since it doesn't pronounce the subject until bar 25.
This is a dance-like three-part variation in 38 time. The same sixteenth note figuration is continuously employed and variously exchanged between each of the three voices. This variation incorporates the rhythmic model of variation 13 (complementary exchange of quarter and sixteenth notes) with variations 1 and 2 (syncopations).
This variation features four-part writing with many imitative passages and its development in all voices but the bass is much like that of a fugue. The only specified ornament is a trill which is performed on a whole note and which lasts for two bars (11 and 12).
The ground bass on which the entire set of variations is built is heard perhaps most explicitly in this variation (as well as in the Quodlibet) due to the simplicity of the bass voice.