J.S.Bach’s Invention 13 in the key of A minor is a movement with some quite delightful shapes to play particularly chord shapes including minor, major, dominant 7th & diminished 7th also in their different positions (root, first & second inversion…) This is an excellent ensemble piece encouraging players to listen to each other. Acoustic instruments can be substituted for the electric ones. The electric guitar and bass guitar are both transposing instruments and sound an octave lower than written enabling the space between the contrapuntal lines to be retained. There are some octave transpositions in the bass guitar part to keep to the instrument’s range. Scores are available in both staff notation and TAB. The guitar is an instrument where the same note can be played in different positions and on different strings. The TAB scores are a literal translations of the notated score and guitar players may well wish to review some of the note positions suggested in these scores. Ornaments are not featured in this movement whilst the realisation plays back at 72 quarter note or crotchet beats to the minute. Accompaniments are in place allowing guitar and bass players to participate in ensemble activities as part of their practice routines. The guitar sounds on one side of the stereo channel and the bass on the other. The accompaniment tracks play back at 58, 60, 62, 64, 66, 68, 70 and 72 quarter note (crotchet) beats per minute. This reflects the fact that the invention can be played at many different tempi. Accompaniment backing tracks are recorded with a dry acoustic to encourage accuracy in playing. There is a two bar count in /click track for each of the accompaniment tracks. As in all the inventions it is a requirement to play accurate note values. Ends of phrases are deserving of particular attention. Legato playing is suggested in the first instance although players can offer their own playing and performance approaches which in many ways is the invitation offered in this and many other Bach music collections. There is no perfectly correct way to play this music and there is the added challenge of being able to re-visit and play the music again. Time spent listening to this work on streaming media will be invaluable to players wishing to understand the different approaches that players have when performing this movement. The principle behind J.S. Bach’s two part inventions is to take a musical idea or motive and then process it following the rules of good contrapuntal writing using the compositional processes of the baroque and at the same time referencing the closely related keys in the harmonic journey. Inversion, repetition, sequence, transposition, rhythmic augmentation/diminution amongst other processes are evident in Bach’s Two Part Inventions as in most music of the baroque period. J. S. Bach composed 15 Inventions in a collection dating from 1723 intended to introduce keyboard players to composition techniques of the baroque. As concentrated and concise movements the 15 Inventions played in an ensemble context present excellent challenges and there is simply not much other music that can better prepare players for this type of music activity. An invention suited to being played by a wide range of instruments possibly with a combination of instruments belonging to different instrument families – a mix and match approach is invited. The 2023 music score is a revision of the 2013 PlentyMusic score.
