Recent demands by composers have included many effects not previously within the bounds of conventional woodwind technique. Avant-garde music, particularly that requiring improvisation, has increasingly required multiphonics, quarter-tones, flutter-tonguing, and harmonic fingerings. I wish to discuss a further technique, a little known part of the bassoon's palette - that of pitch sliding.
Two musical terms are in common use for describing what I call pitch sliding: "portamento" and "glissando." There is some confusion, even among musical dictionaries, as to the exact meaning of these terms, but most make the point that they denote two different kinds of musical effect: a portamento is a gradual and continuous change of pitch from one tone to another, best exemplified by slides possible on stringed instruments, the trombone and the human voice; the glissando, on the other hand, is not a continuous change of pitch, but rather a rapid scale between tones, best represented by the fast, scale-like sweeps possible on the harp and piano.
Among woodwind instruments the clarinet has been able to create successfully both the glissando and the portamento. The opening solo in George Gershwin's "Rhapsody in Blue" is a remarkable blend of trill, glissando, and portamento. In jazz mood-music, commercial jingles, sound tracks and popular music the saxophones and woodwinds have long been requested to scoop, fall-off, and bend notes to embellish melodic and harmonic lines. Glissandi in this style of music are often performed as rapid chromatic scales between notes.
Pre-dating these by centuries is the ancient technique of the Japanese shakuhachi. The player of this end-blown, vertical bamboo flute can scoop and slide notes with very expressive effect.
After discussing the Gershwin clarinet solo with a colleague I discovered that portamenti were possible on the bassoon. Initially I found it easy to slide in half or whole steps up or down with any tones using the finger holes of the instrument if I moved my finger slowly on or off the holes (see Figure 1). Slides of a larger interval involved more than one finger, consequently the coordination had to be more precise. The fingers had to be stiffened (contrary to normal technical practice) and as straight as possible. Bracing some part of the hand on the instrument was helpful in slides using more than one finger (see Figure 2).
Using keys for slides was not as effective as slides on finger holes as the springs on most keys defeat the stow progress required to produce the slide. Harmonic fingerings using keys did produce slides effectively (see Figure 3).
Pitch slides may be classified as follows:
A. Portamenti - such as those playable by stringed instruments and trombones. Playable on the bassoon by fingerings using the tone-holes and by some harmonic fingerings using keys. These may be notated as in Figure 4.
B. Quasi-portamenti - those slides of smaller intervals such as fall-offs at the ends of notes, scoops at the beginning of notes and bends in the middle of notes. On the bassoon these require momentary changes of air speed, air pressure or embouchure to produce. Quick, repeated pitch slides on very small intervals (quarter or half-tones) can be produced by means of an exaggerated vibrato, usually marked "molto vib.". All slides in this category sound best played to pitches below a given tone rather than above it. Notation as in Figure 5.
C. Fingered Glissandi - rapid, chromatic or diatonic scales between tones marked with a straight line and "gliss.". They have been in the technical vocabulary of woodwind players for many years. An effective substitute for portamenti in some cases. Another substitute for a portamento is a very rapid chromatic glissando while flutter-tonguing.
Some things to remember while developing pitch slides on the bassoon:
The bassoon is well adapted to pitch sliding techniques. It has a multiplicity of fingerings for upper register notes and the double reed is extremely responsive to minute gradations in air pressure and subtle changes of articulation.
This article presents only the most basic pitch slide fingerings. There are dozens of possibilities. Perhaps a reader will be inspired to assemble a pitch slide fingering chart. Such a chart would be helpful not only to bassoonists, but also to composers who should know much more about our expressive instrument.