I can free buzz accurate and aurally recognizable pitches using a playable embouchure (One that will work relatively unaltered inside of a large tuba mouthpiece) down to a D four octaves below D in the bass clef… a triple pedal trigger D on a Bb trombone…and I can transfer that buzz (with some compromise, of course) to any bass or tenor trombone mouthpiece including one as small as a 12C. Plus I can freebuzz all of the octaves in between right on up to a Bb above the treble clef.
That is nearly seven octaves. I cannot totally and seamlessly connect all of those free buzzes (Not yet, anyway.), but I can put any and all of them into a mouthpiece/horn combination and make a good trombone sound with them.
Why can’t I connect some of them?
Because I use different amounts, differing masses of lip for different ranges, and there are certain lip settings that get hung up on my teeth when I try to thin them out.
What do I mean by “thin them out”?
Well, imagine that your lips are a string on a violin. I know that the comparison is not perfect, but bear with me here. There are four strings on a violin, and they are pitched (from low to high) in E, A, D and G. Each string is a different gauge…a different thickness…and it is anchored at both ends and stretched to a certain tension. When the violin and strings are set up correctly, each string vibrates very well through a certain range and the available ranges of the individual strings overlap. But of course high notes on the lower strings are not as full sounding as the same notes when played on the higher strings. Furthermore, if you were to take a low E string and install it in place of the higher G string, although you might be able to put enough tension on it to pull it up to a G pitch, if it didn’t simply break first it would undoubtedly sound relatively strained and ugly. Conversely if you tried to replace an E string with a string meant to be used as a G string, you might be able to pitch it to E but it would certainly sound weak in that range because it would not have enough mass to really resonate well in a range for which it was not designed.
What are the essential differences among those various strings?
They have different masses.
Now, imagine that your lips are a reed on a saxophone. You know of course that baritone reeds are generally heavier than tenor reeds, tenor reeds heavier than alto reeds, etc. Why? Because they are built to vibrate well through different ranges. You can force a baritone reed to play in the tenor range, but it is not going to sound very good. You can take a tenor reed, put it on a baritone and get all the notes, but the lower ones are going to be lacking mass and power.
Ok, back to brass embouchures.
We are gifted with the possibility of changing the actual mass of our lips in mid-performance. Almost instantaneously. All brass players do this to some degree, even the ones who say that they play with “one embouchure”.
They roll the lips in and out. In for high, out for low. Sometimes one lip, sometimes the other, and sometimes both. It all depends on the physical makeup of the player. Most of us do this in very small increments. In the classic “pedal shift” people are simply making more of their lip mass available to be vibrated. It is often referred to as opening or dropping the jaw, but that is only a symptom of what is really happening. The jaw must open so that a functioning embouchure can accommodate the greater lip mass.
I have been privileged to sit next to some of the greatest high and low range brass players that the world has ever heard. Lead players like Britt Woodman, John Faddis, Urbie Green, Earl Gardner, Snooky Young and Dave Steinmeyer. Bass trombonists like Dave Taylor, Earl McIntyre and Paul Faulise. Tuba players like Howard Johnson, Don Butterfield and Bob
Stewart. Plus literally hundreds of others of equal abilities and achievement who never cared to become famous enough for their names to be readily recognizable to most musicians. I have watched them carefully in rehearsal after rehearsal and performance after performance. They ALL do this kind of shifting at the extremes.
Until I figured out how to go about using various masses of lip in my own playing I was basically a good two octave and a seventh tenor trombonist. The classic tenor trombone player with a range from a good sounding 7th position, 2nd partial low E to somewhere around D in the treble clef. A player with some available trigger/fake and pedal notes and a relatively unreliable (and progressively weaker as I went higher) altissimo range.
After figuring out this approach and applying it to my own playing?
Like I said…nearly seven octaves of professional level sound and control on any lower brass instrument from a tuba to a small bore tenor trombone.
On my good days.