The BACH motif: how Bach hid an Easter egg at the start of his defining choral work

Bach signed his name at the start of his Mass in B Minor — and it stayed hidden for 250 years.

Music is an excellent vessel for coded messages. There’s so much going on in a piece of music, so many layers to hide messages beneath, they can be hard to spot even if you know where to look. So it should be no surprise that musicians from Shostakovich to Hans Zimmer have buried musical Easter eggs in their works.

One of the first composers to do this was J.S. Bach. He came from a large family of musicians — there are no fewer than 50 Bachs who were involved in music in some way — and it was his great-uncle, Heinrich Bach, who spotted that the letters in the family surname spelled out a musical phrase (in German, the letter H is used for B natural, while B is used for B flat).

J.S. Bach, who had a penchant for including symbolism in his music, famously used this as the start of the last subject (i.e. theme) in the final, unfinished movement of his crowning work for organ, The Art of Fugue. For a lifelong composer, performer and music teacher — who had written over 1,000 musical compositions — to include this in one of his final works can be considered something of a musical signing-off.

Such is Bach’s stature in the history of Western music that many other composers have hidden these same four notes in their own compositions, from his sons to the Romantics Schumann and Liszt; Malcolm Boyd, in the Oxford Composer Companion to Bach, lists 400 such instances. But Bach himself used it sparingly — as Boyd says,

Its presence has been observed elsewhere in Bach’s works… but such instances are not beyond the realm of coincidence.

That is, there are a couple of other times in Bach’s music these four notes crop up — but they come at inconspicuous enough points that it’s not clear Bach had his name in mind during their composition. So, up until now, there’s only been one clear instance of Bach signing his name in his music in this way.

But it turns out there’s another. And its presence has gone unnoticed for 250 years.

Where The Art of Fugue is Bach’s career-defining work for organ, the Mass in B Minor has the same status with regard to his choral music. He wrote the first movements of the mass as early as 1733, but it wasn’t until well into his final decade, in the 1740s, that he really got going turning this into a complete Mass setting — and, in order to do so, he borrowed copiously from his previous compositions, many of which were written for specific occasions in the Church calendar. Unlike most of his choral works, the Mass in B Minor doesn’t seem to have been written for any particular occasion, so it seems likely, as Boyd says, that he reused so much of his existing music in order to enshrine it in a setting that would be sung more often than the existing pieces (Mass settings were used much more regularly), and so help it survive. This would seem a natural inclination for a composer entering his sixties in the 18th-century.

The first movement of the Mass in B Minor opens with a self-contained, declamatory musical statement from the amassed forces of the choir and orchestra. And it’s here, on the first page of a piece that takes 2 hours to perform, that Bach inserted his family’s motif.

The first note is ‘spelled’ differently — it’s an A# instead of a Bb, which it has to be because of the key we’re in. But these are what are known as enharmonic equivalents — different ways of notating the same note. An A# sounds identical to a Bb.

How can we be sure this is an intentional signature on Bach’s part, and not one that can be ascribed to coincidence? I think there are two key clues:

• Its place in the piece. Not only does this signature come in the opening movement of the choral work he wanted to leave the world, but it starts on the third crotchet of the piece, literally the first departure from the tonic chord of B minor that features at the start of bar 1. There is arguably no more significant place in his entire body of choral music that he could have placed a signature like this.
• The harmonic progression. Malcolm Boyd provides a strong reason for a couple of other instances of these four notes in Bach’s work being coincidences: there’s a particular harmonic progression that makes them fairly likely (for the musicians among you, it’s “when the music veers towards the subdominant in the closing bars of a piece in C major”). What happens at the start of the Mass in B Minor, though, is completely different. This is the start of a phrase, not the end — so Bach has complete control over where the music should head, as opposed to being limited to working towards a particular cadence. And what he chooses to do is build the harmony, in the opening of this phrase, around the notes of his name. These are no inconsequential passing notes as part of a cadential resolution; they are notes that lead the way, determining the chords around them. Put another way, you wouldn’t expect to see these four notes in the first two bars of a piece in B minor — unless they were put there intentionally.

Bach was the most skilled composer the world has ever known where it came to figuring out the harmonic possibilities contained within a short sequence of notes – and it seems he found a way of fitting what’s otherwise a fairly unmelodious motif into the introduction to one of his crowning musical achievements, probably just to amuse himself. That he managed to do so in a way that felt so musically natural that it could go unnoticed for so long is testament to his unparalleled compositional skill. Who knows what else lies buried in his music, waiting to be uncovered.