How would Haydn, or any eighteenth-century individual for that matter, tune an organ? It’s hard to believe, but at one point this was quite the contentious issue.
As we examine the debate, yet another question will be answered: why composers compose in different keys. Years ago, I posed this second question to my teacher only to be told that different keys have different colors. They sound different.
Yet, when I cycled through the various keys on my piano, I didn’t really hear much of a difference. True, the minor keys had a different sound pattern than the major. But that was about it. A song composed in one major key sounded about the same played in a different major key.
I thought my ears were at fault. Then I encountered Bach. And a very important clue.
Study the oldest theories on music theory and counterpoint, and you’ll get the impression that the history of music is the history of our gradual acceptance of dissonances. To the medieval ear, intervals of a third and a sixth were intolerable. When we consider that chords are built in thirds, this injunction against them seems inexplicable.
So why was it a cardinal sin to use thirds and sixths? No, it wasn’t because our medieval predecessors were musically very different from us.
Because of the way keyboards were tuned, those intervals did indeed sound harsh and intolerably dissonant.
Naturally, they were avoided and composers used fifths. But it’s hard to restrict a composer in this fashion and by the Renaissance, composers and musicians were demanding a different method of tuning that would make thirds and sixths usable.
The result was something called meantone tuning. A way of tuning the instrument that resulted in beautiful, mostly pure thirds and sixths. That is to say, a string a third above another vibrated in the prescribed Pythagorean ratio of 5:4. Put differently, the upper string vibrates 5 times for every 4 vibrations on the lower string.
The earlier method of having the fifths conform more or less to the Pythagorean ratio of three vibrations of an upper string for every two vibrations of a string an interval of a fifth below it meant that thirds were unusable.
But making thirds usable created a problem. Two problems to be precise. First of all, composers were confined to C major, G major, and F major. Modulating to other keys was simply not possible because of the dissonances involved. And secondly, despite all the minor adjustments to the Pythagorean ratios to ensure they added up to an octave without the kind of jangling that’s heard when two out-of-tune strings vibrate together, there was one fifth that was still awful. The interval between G-sharp and E-flat.
Technically, the black note between the white notes G and A should serve as both a G-sharp (to the right of G) and an A-flat (to the left of A). In practice, sounding out the A-flat and E-flat together in an A-flat major chord created the most gosh-awful sound known to man.
A sound that was referred to as the wolf fifth. Bach had a solution to this problem, and tuned his keyboard instruments using well temperament. The adjustments ensured you could cycle through all the keys and not have to deal with a wolf fifth.
How exactly Bach tuned his instruments is not known. Different tuners had different formulations for getting the best sound out of their instrument. Bach’s tuning method didn’t really catch on. Organ-makers like Silbermann continued to use meantone tuning, and church congregations preferred it to such an extent that it wasn’t until the nineteenth-century that any change was made.
So, Haydn would most likely have used meantone as his method of tuning an organ. Especially, if the organ in question belonged to a church in an entirely different country and would be played by someone other than himself.
If you’re curious, tuning an organ is a two-person job. One sits at the manuals, pulling the stops and depressing the keys the other asks him to. The second person uses a tuning knife to adjust the slides on the pipes, adjusting the length until the interference between the sound waves produced by the tuning fork and the pipe being adjusted disappears.
Modern keyboard instruments use neither meantone nor Bach’s well-tempered method. They use equal temperament. Every key is slightly out of tune, so the differences are spread across the keyboard and our ear is tricked into perceiving no dissonances at all.
This method, first proposed by Galileo’s father, Vincenzo, was long known to musicians, but it was the least preferred solution. Why? Because although you could cycle through the 24 keys—24 different scales—and although you’d never hear a wolf fifth, you would also not hear the individual differences between the different keys.
Since the time I first asked my question about composers and their use of different keys, my ear seems to have developed to notice a slight difference between the various keys. Not so much in character. But it does seem to me that some melodies sound better in some keys than others. Perhaps, I’m deluding myself.
The reason equal temperament was so long widely despised was that musicians could not bear the idea of losing the individual characteristics of the different keys. Harmony as they knew it would be destroyed were that to happen.
I’ve always thought the different pattern of sounds presented by each key would make playing by ear more challenging than it needs to be. On the other hand, perhaps it was this very difference that allowed Haydn to recognize a piece he heard in a London church as being in D major. He was on a walk when he heard the organ, and took a few minutes to notate the melody line in his notebook. These days, you’d have to be cursed with perfect pitch to do that.
This video of Pachelbel’s Canon illustrates how different methods of tuning can affect the music itself. I’ll let you decide for yourself whether the difference is significant enough to be worth the kind of dissent it caused before equal temperament became widespread.
Take a Listen: Pachelbel’s Canon in D.