The marimba ( pronunciation (help·info)) is a musical instrument in the percussion family. Keys or bars (usually made of wood) are struck with mallets to produce musical tones. The keys are arranged as those of a piano, with the accidentals raised vertically and overlapping the natural keys to aid the performer both visually and physically.
The marimba bars, like xylophone keys, are usually made of rosewood, but bars can also be made of padouk or various synthetic materials. Rosewood bars are preferred for concert playing, but synthetic bare preferred for marching band and other outdoor use because they are more durable and less susceptible to pitch change due to weather. The bars are wider and longer at the lowest pitched notes, and gradually get narrower and shorter as the notes get higher. During the tuning , wood is taken from the middle underside of the bar to lower the pitch. Because of this, the bars are also thinner in the lowest pitch register and thicker in the highest pitch register.
In Africa, most marimbas are made by local artisans from locally available materials.
When playing the marimba it is preferred to strike just off center or right on the edge (for the "black keys") for the fullest tone, while striking the bar in the center produces a more articulate tone. Playing on the node (the location where the string passes through the bars) is sonically very weak, so it is only used when the player or composer is looking for that particular muted sound.
There is no standard range of the marimba, but the most common ranges are 4 octaves, 4.3 octaves and 5 octaves; 4.5 and 5.5 octave sizes are also available.
- 4 octave: C3 to C7.
- 4.3 octave: A2 to C7. The 3 refers to three notes below the 4 octave instrument. This is probably the most common range.
- 4.5 octave: F2 to C7. The 5 means "half"; the instrument :4.6 octave: E2 to C7, one note below the 4.5. Useful for playing guitar literature.
- 5 octave: C2 to C7, one full octave below the 4 octave instrument.
The range of the marimba has been gradually expanding, with companies like Marimba One adding notes up to F above the normal high C (C7) on their 5.5 octave instrument, or marimba tuners adding notes lower than the low C on the 5 octave C2. Adding lower notes is somewhat impractical because as the bars become bigger and the resonators become longer, two issues become important. First, the longer resonators present present a difficult design problem involving the necessity of constructing a taller instrument and second, very heavy mallets become necessary.
The marimba is a non-transposing instrument with no octave displacement, unlike some other keyboard instruments, which are pitched one or two octaves higher than written.
Part of the key to the marimba's rich sound is its resonators. These are metal tubes (usually aluminium) that hang below each bar. The length varies according to the frequency that the bar produces. Vibrations from the bars resonate as they pass through the tubes, which amplify the tone in a manner very similar to the way in which the body of a guitar or cello would. In instruments exceeding 4½ octaves, the length of tubing required for the bass notes exceeds the height of the instrument. Some manufacturers, such as Malletech, compensate for this by bending the ends of the tubes. Others, such as Adams and Yamaha, expand the tubes into large box-shaped bottoms, resulting in the necessary amount of resonating space without having to extend the tubes. This result is achieved by the custom manufacturer Marimba One by widening the resonators into an oval shape, with the lowest ones reaching nearly a foot in width, and doubling the tube up inside the lowest resonators.
On many marimbas, decorative resonators are added to fill the gaps in the accidental resonator bank. In addition to this, the resonator lengths are sometimes altered to form a decorative arch, such as in the Musser M-250. This does not affect the resonant properties, because the end plugs in the resonators are still placed at their respective lengths.
The mallet shaft is commonly made of wood, usually birch, but may also be rattan or fibreglass. The most common diameter of the shaft is around 5/16". Shafts made of rattan have a certain elasticity to them, while birch has almost no give. Professionals use both depending on their preferences, whether they are playing with two mallets or more, and which grip they use if they are using a four-mallet grip.
Appropriate mallets for the instrument depend on the range. The material at the end of the shaft is almost always a type of rubber, usually wrapped with yarn. Softer mallets are used at the lowest notes, and harder mallets are used at the highest notes. Mallets that are too hard will damage the instrument, and mallets that might be appropriate for the upper range could damage the notes in the lower range (especially on a padouk or rosewood instrument). On the lower notes, the bars are larger, and require a heavier mallet to bring out a strong fundamental. Because of the need to use different hardnesses of mallets, some players, when playing with four or more mallets, might use graduated mallets to match the bars that they are playing (softer on the left, harder on the right).
Some mallets, called "two-toned" or "multi-tonal", have a hard core, loosely wrapped with yarn. These are designed to sound articulate when playing at a loud dynamic, and broader at the quieter dynamics.
Modern marimba music calls for simultaneous use of between two and four mallets (sometimes up to six), granting the performer the ability to play chords or music with large interval skips more easily. Multiple mallets are held in the same hand using any of a number of techniques or grips. For two mallets in each hand, the most common grips are the Burton grip (made popular by Gary Burton), the Traditional Grip (or "cross grip" used by most professional marimba soloists) and the Musser-Stevens grip (made popular by Leigh Howard Stevens). Each grip is perceived to have its own benefits and drawbacks. For example, some marimbists feel the Musser-Stevens grip is more suitable for quick interval changes, while the Burton grip is more suitable for stronger playing or switching between chords and single-note melody lines. The Traditional Grip gives a greater dynamic range and freedom of playing. The choice of grip varies by region (the Musser-Stevens grip and the Burton grip are more popular in the United States, while the traditional grip is more popular in Japan), by instrument (the Burton grip is less likely to be used on marimba than on a vibraphone) and by the preference of the individual performer.
The six-mallet grip is generally a combination of these three grips. Six mallet marimba grip has been used for years by Mexican and Central American marimbists. Keiko Abe has written a number of compositions for six mallets, including a section in her concerto Prism Rhapsody. Other marimbists/composers using this technique include Dean Gronemeir and Kai Stensgaard.