With stopped horn we get to another interesting and important topic, and also one that is not without some controversy.
As an example, at one point, years ago, someone read my article on stopped horn in Horn Articles Online a bit too quickly and wrote me that what I said was wrong and dangerous. Then, about fifteen minutes later, another E-mail came from the same person that essentially said “nevermind.” In that article, Understanding Stopped and Muted Horn and Right Hand Position, I try to lay out briefly and practically the conventional wisdom. The central part that is confusing is the following.
The burning question many hornists will struggle with is the question of why we think of stopping the horn the way we do on modern horn and why it works at all. The question of what exactly is happening to the pitch of the horn when stopping the bell with the hand has been the subject much study. As noted above, as the bell is closed slowly the pitch goes down but when it is closed very tightly the pitch will rise; some sources say this effect is due to acoustically cutting off the end of the horn with the hand which raises the pitch, while other sources state this is only what appears to happen, as one is actually lowering the next higher overtone to a half step above the previous pitch. The latter approach is correct but in either case, the practical reality is that stopped horn technique as it is taught today for the modern horn relies on this phenomenon, closing the bell tightly and fingering a half step below the desired pitch on the F horn, but this approach to stopped horn technique does not appear to have seen any use before the twentieth century; the hand was always used on the natural horn to lower the pitch of the instrument when closed.
For stopped horn the problem is that the theoretical bumps up against practical reality. In the readings that follow this will be seen to certain degrees.
One initial note I would add as well is over the years I have more and more relied on the use of non-standard fingerings for purposes of intonation, both with students and in my performance. On a large bell horn I feel that I can play well in tune with standard fingerings, but on a smaller bell I feel that I play quite sharp when stopped. By the same token, players with smaller hands seem to as a group have more trouble than me keeping stopped pitch down on any horn. I have found that it helps to develop familiarity or at least the ability to find fingerings that are flat, as these will help bring pitch down. I discuss this further in this article but to quote briefly, “for any note in the treble clef or above there are flat alternate fingerings that work great as stopped horn fingerings for students with small hands.” Many of those are on the Bb horn and are also extremely useful to have available for accuracy.
Hand-stopping is rather difficult to learn, but when the player finally gets the “knack,” it is easily and quickly brought into use. When correctly done, stopping causes the horn to sound a half-step higher. Most beginners feel sure that the theory of the pitch going up a half-step when the horn is stopped is all wrong. They are sure that the tone goes down a half-step and will prove it by demonstrating fingerings that bear out their theory…. This mistaken belief that the pitch goes down a half-step results from almost, but not quite, stopping the horn completely. As the hand gradually closes the bell of the horn, the pitch goes flatter and flatter, until it is almost a half-step flat. It is at this point that the inexpert player quits…. If he would go a little farther and jam the hand quite tightly into the bell, he would prevent the bell from vibrating beyond the point of contact, effectively shortening the tubing (and the bell is part of the tubing) by approximately a half-step. But at this point, the notes must be lipped-up in order to jump this half-step upward. The pitch will not jump up of its own accord but must have aid from the lips. When correctly done, the “open” arpeggio on the F horn will sound perfectly in the key of F sharp, proving that the pitch of the horn has jumped upward a half-step. This peculiarity requires the horn player, therefore, to always transpose down a half step when playing stopped notes.
Ideally you should be able to swing the hand shut from your normal open position, “exactly as though one were swinging a door closed.” Farkas also notes
One important warning: stopping can be done only on the F horn. Stopping the B flat horn results in a pitch rise of almost three-quarters of a tone, and of course there is no way to compensate for this with transposition. Some single B flat horns have a special valve which not only corrects the pitch but also automatically transposes down a half step. But, generally speaking, one cannot stop the regular B flat horn and play in tune.
Speaking of stopping valves, they work great. If you are unfamiliar with what they are, check this article for more information. Mostly seen on descant horns and single Bb horns today, these are “the best invention ever.”
There is much more to say on this topic and we have more next week, stay tuned.