A few weeks ago we looked at the capability of instruments to make a variety of changes to their usual timbre. We examined the history of pizzicato and col legno, just a couple of tools in the string department’s box of tricks. String instruments have arguably the greatest range of alternative voices, but they are more than matched by other instruments in some performance techniques. And not just instruments. The human voice can also surprise. If you are unfamiliar with overtone singing, then check out this performance that features a mesmerising example of Mongolian throat singing, spiriting up two notes from a single larynx.
String instruments can also play two notes simultaneously on adjacent strings, and fake it for triads and four-part chords by moving the bow rapidly across the others. J. S. Bach‘s Ciaccona from his Partita in D minor for solo violin (8.570277-78) is a wonderful example of this technique that is often used to virtuosic effect, such as in No. 20 from Paganini‘s 24 Caprices for solo violin (8.550717). A horn player friend of mine once showed me his party-trick of playing a note whilst humming another which intriguingly produced a third from out of nowhere to magically complete the triad.
Harmonics is the term used when a string player’s finger lightly touches a string, producing a much higher, ethereal soundthan normal. There are two types, notated respectively by a small circle and a lozenge-shaped character. Mahler used this colour at the opening of his First Symphony, Titan (8.572207) to portray the eerie, still atmosphere of “nature’s long sleep of winter.” Playing harmonics is also often integrated into virtuoso technical displays. The legendary 19th-century double bass player/composer Giovanni Bottesini gives a good illustration in his Variations on Nel cor piu non mi sento from Paisiello’s opera La Molinara (8.570400). You may occasionally find yourself rubbing your ears in disbelief that you’re listening to the basso profundo of the string department.
Guitars and harps also produce the sounds of harmonics, while examples of double harmonics on wind instruments, produced by over-blowing, can be heard in Berio‘s ‘Sequenzas’ (8.557661-63), specifically No. 7 for oboe, and 7b for soprano saxophone.
When singers connect two notes with a gentle swoop, it’s known as portamento; when the effect is called for on an instrument, it’s know as a glissando or ‘slide’. The trombone is well equipped for this effect; it’s principal visual characteristic is the moving part of its mechanism, appropriately called the slide. Often used for comical effects, a popular example can be heard in J. A. Greenwood’s The Acrobat.
Other examples include the opening bars of Gershwin‘s Rhapsody in Blue (8.559750), which features possibly the best-known glissando for clarinet. Messiaen’s Turangalila Symphony (8.554478-79) ushers in its first principal melody with a sleazy glissando for full strings; shortly afterwards the ondes martenot makes its first appearance, swooping erotically between its electrically generated sounds.
Virtually all instruments can be played muted, reducing the sound to a more muffled quality. The left pedal on the piano(notated as una corda) serves this purpose; Liszt‘s Libestraume No. 1 (9.80492) opens with the instruction to produce this sound. On string instruments, a small device is clipped onto the bridge to achieve a distant tone; you can hear how Prokofiev used the effect near the start of the opening movement of his Romeo and Juliet Suite No. 2 (8.571210).
Apart from the flute, wind instruments usually mute themselves by rather unceremoniously stuffing a handkerchief into the bells of their instruments; you’ll occasionally hear conductors telling the bassoons to “put a sock in it”. Brass instruments boast the largest selection of mutes that alter their sound with a wide variety of timbres. The line-up includes Straight, Cup, Wah-wah, Bucket, Derby and Plunger. One of the more practical options for brass players living in thin-walled apartment blocks is the near-silent Yamaha practice mute that is equipped with a built-in microphone connected to a headphone output.
The third movement of Alban Berg‘s Four Pieces for clarinet and piano demonstrates the use of the flutter-tonguingtechnique, whereby the plays rolls the tongue to produce a growling effect. Another example occurs during Richard Strauss‘ Don Quixote (8.554175), a tone poem relating the fantastic adventures of a whimsical knight. After attacking a group of windmills, which he mistakes for a collection of giants, Don Quixote then mistakes a flock of sheep for the sound of gathering armies. The sheep are vividly portrayed by the use of flutter-tonguing in the brass.
Finally, a mention of circular breathing, more an amazing technical feat than a tweaking of timbre used by wind players. This requires breathing in air through the nose and expelling it through the mouth, while keeping a reserve in the cheeks, enabling the players to produce unusually long melodic phrases. Stretches of Richard Strauss’ Oboe Concerto require the technique, but it’s more readily demonstrated by tapping into any performance by a seasoned Australian didgeridoo player.