Published on Sunday, 25 April 2010 15:56
Written by Bruce Gale
Contemporary composers often require brass instruments to be muted in order to achieve certain special effects. Generally speaking, mutes raise the pitch of an instrument, especially in the lower register, and this factor must be borne in mind during performance. Because mutes also add resistance, some band directors recommend that their students practice with them as a means of building up embouchure strength. The value of such practice is debatable, however. After all, it is difficult to work on tone quality when an instrument is muted. My reservations here also extend to so-called "practice" mutes.
There are also mutes for tubas, euphoniums and French horns.
Trumpet players are the most likely to play music demanding the use of a mute (often indicated by the words con sordini or avec sourdine in the score). Trombone players may also come across similar instructions. Although rarely used, special mutes are also available for tubas, euphoniums and French horns. The general rule of thumb when using a mute is to play one dynamic level louder then written.
In order to ensure a good blend, it is important that mutes made of different materials or produced by different manufacturers are not mixed within a section. Mutes vary widely in sound quality and intonation tendencies, even when they appear to be of the same general design.
There is an entire range of specialised mutes, each producing its own characteristic timbre. Some of the most common are discussed below.
The straight mute is the most basic, It is also the one you should use if the composer fails to specify which type of mute he requires. The conventional straight mute can be made from plastic, fibre or aluminium and come in both conical and pear shapes. The most popular, however, is the pear shaped mute made of aluminium.
The straight mute produces a sharp, bright sound.
All straight mutes have three or four strips of cork down the side to hold the mute in the bell of the instrument. The quality of the sound can often depend on the size of these corks. Thick corks tend to produce a more open sound and free blowing response. Because the bell throats of different model trumpets and trombones vary in size, the corks may need to be sandpapered down a little to achieve a proper fit in the bell. The straight mute produces a sharp, bright sound, with a rather thin tone.
A cup mute is little more than a straight mute with a cupped resonator attached to the end. Primarily used in jazz ensembles, cup mutes tend to affect normal playing less than any other type of mute. Some players experiment with the sound by stuffing cloth or other soft material into the cup. Somewhat surprisingly, cup mutes sometimes tend to lower rather than raise the pitch, particularly in the middle register. A cup mute produces a velvety tone quality.
The harmon mute looks, sounds and performs quite differently from the straight mute and the cup mute. It consists of a thick cylinder with a partial cone on one end. This cone is the part that fits into the bell. Unlike the straight mute and the cup mute, it has a solid ring of cork that does not allow any air to escape except through the mute. At the other end of the cylinder, there is a detachable stem that extents through the centre of the mute.
This mute is more difficult to play.
The harmon mute produces a piercing, strident sound. Extending or removing the centre stem, however, can darken the tone quality. Unless otherwise indicated, harmon mutes are played with the stems removed. The notation stem in and stem out calls for the stem to be placed all the way in or extended as far as possible. This mute is more difficult to play than other types of mutes. This fact often causes the performer to play sharp, particularly in the middle register. The low register, on the other hand, is sometimes flat.
The harmon mute can also be used as a wah-wah mute. This is done by covering the bell with the left hand. The symbol "+" indicates that the hand should completely cover the bell, while the symbol "o" indicates completely removing the hand.
Other mutes include the solotone, the whisper, the plunger and the hat. The solotone mute looks something like a straight mute within a straight mute, but with a solid band of cork to grip the bell and force the vibrating column of air to travel through the mute. It has a soft, dark sound that lacks the brassy quality of the harmon mute. The whisper mute looks a bit like a conical straight mute. Like the harmon mute and the solotone, however, it has a solid cork band to hold the mute to the bell. A tightly fitting resonator filled with felt ensures a soft, remote sound. Both the solotone and the whisper mute can be difficult to play, and the performer has to work hard to ensure that he does not play sharp.
The hat mute changes the tone quality the least.
Several other mutes clearly have their origins in common objects. The plunger, for example, can consist of nothing more than a regular plumber's plunger. It is used to produce sound effects in a similar manner to the wah-wah. Plunger mutes manufactured especially for the purpose are usually made of aluminium. The hat mute changes the tonal quality of the instrument the least. In this case, an ordinary hat stuffed with cloth can be used. The hat is held directly in front of the bell (but without touching it), to produce a sort, far-away quality. When found on a score, the term in hat can also include similar effects produced by other means such as playing into the music stand or tying a cloth bag around the bell.