Living Water - Dissertations - Bass Ringer's Notebook - Sustained Sounds

Sustained Sounds

There are two basic types of sounds we make with bells. Sustained sounds involve allowing the bell to vibrate for some (nontrivial) amount of time before damping it (see the next page for stopped sounds). These fall into a couple of rough categories (and if you don't, feel free to make your own grouping...): Non-overtly Dopplered sounds and overtly Dopplered sounds.

(To which you might have said, "Huh?") Back in 1842 (the centennial of the composition of Handel's "Messiah, incidentally), a gent named Christian Doppler presented a paper entitled "On the coloured light of the double stars and certain other stars of the heavens". That's to say that he'd determined that if a radiant object is moving toward or away from you, the frequency of its light, and therefore its color, changes according to its speed. He also found, much more easily, that the same thing happens with sound waves. If you do the math/physics, you can produce a noticable change in the frequency emitted by an object by moving it along the line to the observer at a speed as low as three or four feet per second if the velocity is changing sufficiently quickly to provide the listener with a short-term frequency frame of reference.

All that is to say that you don't have to move the bell or chime very quickly to make its perceived pitch change, much in the same way a police siren changes pitch as the car flies past you, hunting for the bad guys. So, anyway, "overtly Dopplered" refers to sounds we make which deliberately use the Doppler effect to change the perceived pitch, and all the others are "non-overtly Dopplered".

Non-overtly Dopplered sounds:

• R (Ring): When we ring a bell, we're not actually trying to implement a significant Doppler effect as we make the circle. But because you know that pitch changes with velocity-in-the-direction-of-the-audience (since God is omnipresent, does He worry about the Doppler effect?), you understand that there'll be a teeny bit of pitch variation - that's what makes the tone of a moving bell richer than the tone of a nonmoving one. When you make" the circle", the sound waves which leave the bell later are Doppler-shifted slightly higher from the ones which leave the bell at the bottom of the stroke. On the top half of the circle, the pitch is Doppler-shifted slightly lower because you're moving the bell away from the listener. The result is that, rather than hearing a fundamental pitch which consists of one pure frequency, you hear a somewhat "fatter" pitch - that's the same reason a group of instrumentalists (who are in reasonable tune with each other) sounds richer than just one of the players. If you don't give a hoot about the physics (Jaylene says, "It's all physics...") with which I've just regaled you, please just remember to make the circles.

• ,~~~ (Shake): I'll be the first to admit that there will be some amount of Doppler effect when you shake a bell; however, it's overpowered thoroughly by the clapper strikes at each end of the shake. You might also note that when the clapper strikes, the bell is reversing direction (i.e. has zero instantaneous velocity), so the pitch you get there is the same whether it's at the front or back side of the motion. In general, though bells below C4 don't get shakes because big bells are hard to shake, even when moving them around their centers of gravity - and even more, low shakes have a tendency to sound ugly.
  
  Additional technical thought: If you remember to use your "katana grip", try also putting the "loose grip" fingers on the edge of the handle to add a little more control and power to your shake. When I do this, however, I do it only for long shakes just because it takes time to move the fingers to their alternate grip locations.
  
  Shakes don't work very well with chimes because the clapper works in only one direction. You'll need to decide (with your director!) exactly how you want to handle this. An alternative is to "shake" the chime an octave higher with it, but this isn't entirely satisfying.

• Echo: To do this, you ring the bell, then touch it to the pad lightly and lift, producing a sort of "wah" sound. Yes, the bell is moving, and, yes, there is a Doppler effect, but since the motion is vertical, the pitch shift won't be audible to anyone unless they're above or to the side - and that means the audience won't hear it. All they'll hear is the wa-wa-wa of the (usually repeated) echo.
  
  It's difficult to perform an echo with chimes because so little pad contact is required to kill the sound. However, you can get a creditable result if you 1) use a large enough chime, and 2) touch only one corner of the chime to the pad.

• (Mallet off the table): You can strike a bell held or suspended off the table with a mallet. This produces a much less percussive sound than the clapper does. It usually appears in soft passages. This turns out not be to be very effective technique for mallets as it makes nearly the same sound as the clapper.

Overtly Dopplered sounds:

• , (Swing): Ring the bell normally, then swing it behind you (BE CAREFUL THAT YOU DON'T WALL-MART!!!), then swing it back to the original position. If, as more and more is the case, the arrows are used, they occur at the beats in the measure where you swing down and swing up. Sometimes the beat numbers are also provided. You can also execute a swing with a chime, but keep the tines pointed up or forward to protect them.

• vib. (Vibrato): For bells, wave the bell in a left-to-right oscillation. The bit of Doppler effect you hear is due to the minutely changing distance between the bell and the audience. Because the motion is fast and short, you'll achieve the requisite 3-4 feet per second speed easily. Vibrato is minimally effective with chimes, probably because of the orientation of the tines (you might want to experiment with turning it sideways) - but there's a special chime technique by that name: Play the chime, and then repeatedly touch a finger to the side of one tine to produce a volume- (rather than pitch-) based vibrato.

• (Gyro): Ring the bell normally, then rotate it in a roughly horizontal plane (like the red and blue lights on top of a police car). With small bells, there's a tendency to want to make the bell too horizontal; this can do bad things to your wrist (just try it without a bell and you'll see what I mean). With a large bell, this risk is even higher, so be careful. The best solution, in my opinion, is to rotate the bell as horizontally as possible, but to make it rotate around its center of gravity (using, of course, the "katana grip" to protect your wrist). Note: You don't need to be all that horizontal - that's the "show" effect of the gyro - you just need to be close enough for the "siren" effect to happen.