Prelude & Fugue in Bm, Book 1 Well Tempered Keyboard J.S.Bach (1685-1750)
"How Firm a Foundation"
This week is the last of my three selections from Bach’s Well-Tempered Keyboard (and for the next three weeks we’ll have ‘easy listening’ preludes to clear the palette!), exploring the theme that ‘less can be more than enough.’ After all, this landmark collection of pieces was composed for a four-octave student keyboard — about half the size of the piano keyboard. (Even cheapie keyboards from Walmart are larger.)
‘Well-tempering’ has its own history. If you do your acoustical physics, it turns out that D-sharp is not the same as E-flat, and so on. So the players of string, brass and woodwind instruments tune themselves on the fly to their fellow players. Keyboard instruments, however, cannot do this. Amazingly, it was the mathematical-musical-mystic Phythagoras (fifth century BCE!) who first figured this out. So, on a keyboard instrument it’s not possible to have all the notes in tune with each other. (Well, you could if your keyboard had an infinite number of keys, but that presents its own challenges.)
The dominant tuning system for keyboards in the Renaissance was called ’just’, and the idea was to have a few keys in really good tune (like C, F and G – keys with just a couple sharps and flats). And the rest sounded really hideous (like Gb major with 6 flats).
But as music progressed down through the centuries, composers (and listeners) wanted to have a greater range of useable keys. So in the Baroque era, ‘mean tuning’ became the norm, in which they spread the error around more: C, F and G weren’t in as good tune as with just tuning, but they were still usable, and now other keys like A and Eb were available. (Gb major still sounded hideous.)
But of course music continued to evolve, and by the 18th century composers were becoming interested in ‘extreme’ keys like Gb, so ‘well-tempering’ was invented. The idea was to spread the error around more or less equally to all the keys. With well-tempering keys like C, F and G have less error than Gb major, but now even Gb major was usably in tune — one could finally use all twelve keys: A complete ’one musical world’ that encompassed all the keys, not just a privileged few.
And finally, in the 19th century, the musical world settled on ‘equal tempering’, in which all the keys are equally out of tune. (We’re just used to it, like living with smog your whole life.) And that’s the system we use today for tuning keyboard instruments.
I personally don’t think the evolution of keyboard tuning systems is ‘progress from the nasty primitive just tuning system to our wonderful modern equal temperament’ — something was lost when we homogenized all the keys to be identical. With well-tempering each key really did have its own ‘color’ — the keys didn’t all sound identical. But with equal temperament we have something like a ‘wonder bread’ tuning system in which all the individual character has been expunged into a pasty sameness.
Meanwhile, back to Bach. In his Well Tempered Keyboard he wrote a prelude & fugue in each of the 12 major and minor keys. Ever pushing his own boundaries, the last fugue in the set uses a fugue subject which itself uses all 12 notes! Something that no one had done before. After this piece, the use of all 12 keys equally didn’t reach full force until the late 19th century (musical ‘chromaticism’), and in the 20th century a composer named Schoenberg (1874 – 1951) invented a musical composition system called ’twelve-tone’ in which the only ’melodies’ permitted must use all 12 notes. (Schoenberg’s 12-tone music is rather hideous listening by general consensus. Check it out on YouTube — or not.)
Bach’s ’twelve-tone’ fugue, however, is beautiful. But strange – so much chromaticism is still strange even to our 21st century ears, and the feeling of the piece – to me at least – is something like "Toto, we’re not in Kansas any more". Or that feeling when you thought you had everything figured out and you suddenly realize that what you were so sure about ain’t so.
So what can you do with a puny little four octave student keyboard? Oh, not much — just discover a new musical continent where no other composer would venture for another century and a half.