So recently while working on a transposed Arban interval study to incorporate the F-attachment, I had an epiphany about how the valve needs to work—just like the slide: i.e., one position or the other—here or there—up or down—"click" or "click". Duh… again.
But just like my Duh with the valves, it’s amazing how many trombonists don't get this when it comes to slide technique. When changing notes with a valve, it's obvious—there is no in-between unless you're going for an effect of some sort. Doc Severensen says to really "bang the valves down." My concept has always been the same for trombone slide motion: it should be in one place or another, but never in between (excepting for glissando or portamento).
But inevitably, when I tell a student to speed up the slide motion to get the syrup out of their legato, they will do one or both of two things: choke the air between notes (out of sympathetic tension in the throat), and/or rush (because they're accustomed to leaving the previous position too soon).
I advocate practicing with no tongue to work on the former. I advocate studying quantum physics to address the latter.
Not really. But a physicist named Werner Heisenberg has a theorem named after him for discovering that subatomic particles (an electron, for example) can't be said to be located in a particular place at a particular time; they don't exist in the way that, say, a baseball does in the macro world. On our conscious level of perception we're either here or there, moving this speed or that. If we want to get from Atlanta to Chicago, we know which direction to go. And the faster we go, the sooner we'll get there (barring speeding accidents).
Not so with the electron. Instead, physicists talk about mathematical probabilities—a wave state of where a particle is located or it's velocity, but not both simultaneously. There is an uncertainty that only observation makes concrete, or “real.” At the time, the philosophical connotations for this were staggering—passive observation affects reality. Einstein rejected it; but he was wrong (still a pretty smart guy, nonetheless).
What's spookier (to use Einstein's words) is when particles are "entangled" at the quantum level (in pairs). Let's say one particle in the pair has a clockwise spin; it's entangled "partner" will spin counterclockwise . If we change the spin of one, the other will change as well. But here's what's spooky—it's simultaneous, even across vast distances. Speed of light ought to be fast enough for an electron (or a trombone slide), but this is not just fast—it’s instantaneous. (Theoretically, that would be even better for legato playing.) But Einstein didn't buy it. He's the one that coined it "spooky action at a distance".
I'm not qualified to demonstrate why Einstein was wrong. (Don't feel bad for him; he gave us two theories of relativity and a theory about how gravity operates as waves in space-time that has just been proven after 100 years.)
But trying to move a trombone slide faster than the speed of light (impossible according to Einstein) doesn't work so well, because trying to move the slide faster from point A to point B only results in jerkiness, rushing, and bad air flow. However—there is another solution!
Sometimes, if I get fed up enough with a student who can't begin to approach these challenges, I'll tell them in all earnestness, “Stop moving your slide between 4th position and 1st position” (in order to play, say, a G in 4th, to a B-flat in 1st).
After questioning me about alternate positions (of course there are none) and then looking at me dumbfounded and asking the obvious, "then-how-do-I-play-the-right-notes?" I'll tell them that “motion is inherently impossible.” Huh?
Well, for the car to travel from Atlanta to Chicago, it of course, must travel halfway first. That's great, we're halfway there—or are we? There's still that remaining distance to cover and we obviously must move half of that first. We're closer, but at this rate we'll only ever get closer and closer, but never the full distance.
Obviously it doesn't work like this because the car (or slide) is continually moving. But that's the point: IF IT'S MOVING, THEN IT'S NOT THERE YET. So you're late; or you're sloppy; or you're smearing; or you're stopping your air to cover all the preceding bad adjectives.
The answer is: Remember your quantum physics. Don't move it between the notes. Don't move it to the note. Move it for the note—when it's time to play the note. Not fast, not slow. One place or the other. No in-between. And if there's a note to play between two other notes, guess what the slide has to do? Stop there, too—be one place, then the next, then the next. Never moved, never in-between.
All matters of infinite regress and naïve descriptions of physic aside, there is a practical example we could look to, and that is the old-fashioned movie camera. What appears to be continuous, connected motion is actually discreet, still frames. But they're so brief that the brain does not detect the stops.
So maybe there is an optimal speed for the slide to move that is slow enough to be executable, but fast enough to enable our sound to be continuous enough for our brains to interpret it as "connected." But again it's not a speed we "measure" because the speed is not the goal; connecting the notes is the goal.
Spooky action at a distance. Quantum Trombone.
(Einstein was a violinist, by the way. What do they know?)
SEE also: https://www.technologyreview.com/s/427174/einsteins-spooky-action-at-a-distance-paradox-older-than-thought/