TBC Ep 9 | Sonata for Flute in G minor, BWV 1030a (Mvt 1)

“The Mystery of Bach’s B minor Sonata”


Tiny Bach Concerts Episode 9: Remarks and performance by Mary Oleskiewicz, flute and David Schulenberg, harpsichord


David Schulenberg: Bach composed mainly for keyboard instruments and the voice. Yet a few well-known compositions for instrumental ensemble loom large in modern concert programming. Although those compositions are familiar to many concert goers, their history is rather mysterious. Many, perhaps most of them, were originally written in versions other than those which we know today. With few exceptions, we don’t know when, where, or for what instruments Bach originally wrote them.

Mary Oleskiewicz: The sonatas for flute are particularly enigmatic. The flute sonata in B minor is among Bach’s most frequently played chamber works, and it is one of the very few flute works for which we have Bach’s autograph score. Yet as with the majority of Bach’s compositions for instrumental ensemble, it is by no means certain when it was written, or if Bach originally composed it for flute and harpsichord, the instruments called for in the surviving sources.

DS: The sonata actually survives in two versions, in fact, at least partially. Both versions are in three movements; we will play the first movement, which is the longest and most complex. The familiar version of the sonata, which is the one that survives complete, is preserved in a manuscript that Bach wrote out around 1736 in the German city of Leipzig. There Bach had been serving as cantor and city music director since 1723. By 1729 he was also directing public concerts by the Collegium Musicum, a sort of musical club. It’s possible that he prepared this sonata for one of those performances.

MO: Yet the music probably was not new at that time. We know this because there is another, later, manuscript of the sonata, written not by Bach but a copyist. This copy contains only the part for a keyboard instrument, and it’s written in a lower key, G minor. The title page indicates that there should also be a flute part, but this is missing. Nevertheless it’s clear that this manuscript, although dating from after Bach’s lifetime, preserves an earlier version of Bach’s composition.

Scholars have wondered whether this early version of this sonata was actually for other instruments. Oboe and violin have been suggested in place of the flute. There even exists a modern edition of the sonata in G minor arranged for oboe and harpsichord. But the editorial oboe part cannot be played on the Baroque form of the instrument that Bach would have known. This is one of several reasons why the early version of the sonata is unlikely to have been intended for the oboe.

DS: Another suggestion is that the mysterious keyboard part in G minor was originally meant for the lute, which was an ancestor of the guitar. According to this hypothesis, Bach first composed the piece for lute and violin. Although he later created the familiar version for flute and harpsichord, somebody else subsequently arranged the original lute part for a keyboard instrument. Yet the music is not particularly well suited for either lute or violin, and nobody has yet offered a hypothetical reconstruction for those instruments.

A more convincing suggestion is that the G minor keyboard part was for a so-called Lautenklavier, or lute-harpsichord. This was a special harpsichord designed to sound like a lute. No actual lute-harpsichords survive, but we know that Bach owned one. We can fake the sound of that instrument by using the so-called lute stop of a normal harpsichord [DEMO].

MO: An argument in favor of the lute-harpsichord is that it helps explain the unusually low register of the G minor keyboard part. If the G minor version was indeed for the flute, as I believe, then the flute part presents a more serious problem. All of Bach’s surviving flute parts are for the typical Baroque flute, a wooden instrument approximately two feet in length, whose lowest note is D above middle C. However, this ordinary flute does not have a range that allows it to play the sonata in the key of G minor.

We know, however, that there were larger versions of the flute available in Bach’s day. One of them, known as the flute d’amour, or the flute of love, played at a pitch about a third lower than the regular flute. This instrument is a flauto d’amore (flute d’amour). It was made by the Montreal flute maker Boaz Berney, after a Dutch instrument from the eighteenth century. This is a regular Baroque flute. It is a copy of an Italian flute made by the German maker Martin Wenner. I’d like to play the instruments for you back-to-back, small to large. [DEMO]

The early version of Bach’s B minor sonata may have been meant for a flute d’amour. Although no surviving music by Bach explicitly calls for it, we know that other composers wrote for it, including some of Bach’s contemporaries. If Bach did originally write this sonata for a flute d’amour, it would have been a quite special piece unlikely to receive many performances. Bach might have created the more familiar version of this sonata in B minor in order to make it playable on the more common flute in D.

Nevertheless, when combined with the lute-harpsichord, the larger and deeper flute d’amour produces a lovely, somewhat darker sound than what one usually hears in performances of this sonata. In addition, the gentler volume and clarity of the lute-harpsichord provide the perfect complement for the softer, rounder tone of the low flute. Although we will be performing only the first movement for you, it is worth mentioning that this pairing is also very effective in the second movement where Bach inexplicably wrote out thick and full lute-like chords to accompany a very delicate flute melody. Interestingly, one surviving flute d’amour in Bach’s circle¸ attributed to the composer and flute maker Quantz, transposes at a major third. That is precisely the interval needed to perform the B minor flute part with a keyboard playing in G minor. Such a flute may offer evidence as to why the G minor keyboard part survives without a flute part in the same key.

DS: The most substantial differences between the two versions of the sonata are found in the first movement. Apart from the difference in key, however, even in the first movement the distinctions between the versions in G minor and in B minor concern only details. Unless you happen to know the sonata quite well, you are unlikely to notice the differences, other than our use of a distinct form of the flute. We can’t be certain that Bach originally meant the B minor sonata to be played by flute d’amour and lute-harpsichord. But we believe that this previously unheard version of Bach’s sonata is a plausible solution to one of the mysteries of this extraordinary composition.