November 28, 2013

On the intricacies and atrocities of playing the French Horn – guest post by Midget


My very favorite joke* about the french horn is “How do you know the horn is a divine instrument?……Man plays it, but only God knows what comes out.**”

I love this because it is the Gospel Truth. Even after playing the horn for more than half of my life (at this point, a good deal more than half), there are some days in which the sounds that come out of my bell are as mysterious as the dark side of the moon. Or a hellhound’s inclination towards food.

“But why?” you may ask. “The thing only has three buttons, surely it can’t be that hard.” Ah, if only it were that simple. All instruments operate on one basic principle: they use vibration to produce sound. For a piano, a hammer strikes a string when you press a key. For a violin, the friction between the bow and the string causes that string to vibrate. For a wind instrument, you rely on a vibrating column of air. For brass instruments in particular, you make the air vibrate with your face. Basically you blow a controlled raspberry into your horn. Classy, right?

The fundamental problem of the air-vibrating method of sound production is that a specific length of air column will only vibrate at one set of specific pitches, called a harmonic series. These pitches are the products of the intersections of sound waves in the air column (my understanding of acoustic physics starts to break down at this point, so I can’t tell you exactly how to visualize this). So for one specific length of vibrating air you get around 16 pitches unevenly spaced over a span of 4 octaves, although only about 8 are usable and most of the pitches are crowded together in the highest octave (see visual here). This is why hunting horns and bugle calls have such an iconic sound: they only have a few notes to work with, so they make the most of ’em.

The french horn originated as a hunting horn. Baroque and Classical composers took it out of the fields and into the symphony, mostly for the purpose of having horn calls in their programmatic music. You can hear some of them in Mozart*** and Beethoven. For a long time the horn was just a length of tube with a mouthpiece and a bell, and if a composer wanted a song with horns in a specific key, the hornist just swapped out one length of horn for another to get the eight notes the composer wanted in the right key. Eventually, they realized that if you could add length to your basic horn with extra bits of tubing you wouldn’t have to have ten or a dozen horns, and thus the idea of slides (or crooks, as they were called) was born. So when a piece came up in, say, G major, the hornist would just pop the correct crooks into his horn and be ready to go.

By and by some smart person developed valves, which let the crooks become a permanent part of the horn. By depressing a valve you open up the corresponding slides (crooks) and thus lengthen the available tubing, which changes the series of pitches you can play. So basically, you use your valves (singly or in combination) to pick your series of available pitches, and then choose the specific pitch you want to play by blowing a highly controlled raspberry into the horn. The smaller the raspberry, the higher the pitch, and visa versa.

This whole arrangement of valves and crooks lets you play chromatically, which is a great improvement on the eight-pitch scheme, but there’s a catch. The french horn’s “normal” range is set quite high in the harmonic series, where all the notes are smushed together. This means that for any one note there are at least two valve combinations (furthermore to be known as fingerings) that will let that note play^. The higher you go, the more fingerings there are for any given note. So it’s not uncommon that you come in on what you think is the right note and can play merrily along for several measures before you hit a note that will not work with the fingerings you are trying to use–and then discover that you’ve been a third lower than you should the entire time.^^ As I said, only God knows what comes out!

(Other adventures include: High Notes {and shattering them like clay pigeons in skeet shooting}, Transposing, Hand Stopping, and the Invidious Gurgle. And playing Wagner {and Holst/Mahler/Reed} really, really, REALLY loud.)

* * *

*and I know loads of terrible instrument jokes

**Incidentally, my horn is named Amadeus, which means “Gift of God”. He’s a beauty. Well, actually, he looks like he’s one step short of scrap metal–old, big, and unlacquered, which means nothing I can do will keep him from tarnishing–but dang, that boy can SING.

***Mozart wrote four horn concertos and all of them have at least one movement (usually the third) that’s based on a hunting horn call. This is the third movement of the third concerto:

^This whole harmonic series/extra fingering thing is further complicated by the fact that the modern standard horn is a double horn. It has TWO sets of slides/crooks (in the keys of F and B flat) attached to the valves, and comes equipped with a trigger to swap between the sets of slides. The reason for this is that some parts of the horn’s range are easier to play and/or better in tune on each set of slides. But it quadruples the amount of fingerings you can use, which can be extremely confusing.

^^This phenomenon makes sight reading a (bigger than usual) ratbag on days when my sense of pitch is off. Come in on the right pitch? Ha, forget it. And when the whole horn section is having an off day, we all just kind of glance shiftily at each other as our entrance approaches, hoping someone will A) have counted their rests correctly so we know when to come in, and B) get somewhere within a fifth of the correct pitch. In Classical or Romantic pieces you can often use the harmony to make an educated guess about the correct pitch, but if it’s a contemporary piece, you just wing it and hope it fits into some chord some where.

Dream no small dreams for they have no power to move the hearts of men. –Johann Wolfgang von Goethe


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