A Bach Triple Concerto

I'm trying not to talk about musical things my readers are not familiar with, so: what's a Concerto, again? It is a piece of orchestra music, featuring a solo instrument; in other words, that instrument is given a very prominent part in the piece.  (These days, piano concertos are some of the most common, but in the time of Bach, for instance, concertos were written for all sorts of solo instruments.  The one I'm going to write about is a triple concerto.  The instruments are flute, violin, and oboe.

Now remember, Bach died in 1750, which is centuries ago, so a lot of what we know about him has to be painstakingly dug up, and we only know about this flute / violin / oboe concerto from indirect evidence, but the evidence is very strong.

Around about 1735, Bach applied to work at St. Thomas's School in Leipzig.  The job involved teaching, and training the choir, and providing music for church services.  Being an energetic guy, he also undertook to provide live music at a certain Zimmermann's Coffee Housein Leipzig.  Now, at his earlier job, Bach had written numerous orchestral pieces to be performed by the modest orchestra of the Duke he had worked for.  About half the music from that time never came down to us, but we have catalogs, which tell us what sorts of pieces he had written.  In Leipzig, Bach's three oldest boys were around 20, and he (and they, probably) wanted to display what they could do, and they being skilled harpsichord players, Bach rewrote some of his older multi- instrument concertos for various numbers of harpsichords.

There is also a concerto for three violins, which is well known.  It was evidently the work that was the origin of the three harpsichord concerto!  In fact, Bach was well known for borrowing his own music, and cannibalizing it to write more music for different instruments.  Most interestingly, musicologists (sort of musical detectives) studied the triple  harpsichord concerto, and the triple violin concerto side by side, and, as you can imagine, learned a ton about how Bach went about converting one type of concerto into the other!  If modern-day composers were to go about doing this, they would possibly do it differently, but musicians have been insanely fascinated with Bach's methodology for a long time, so this process of comparing concertos was fascinating. 

But, listen to this.  They studied the violin triple concerto, and decided that that was also a conversion from an as-yet-unknown earlier concerto, for different instruments.  So, working backwards, they reconstructed this triple concerto for flute, violin and oboe.