Tuning

The double bass is generally tuned in fourths, in contrast to the other members of the orchestral string family, which are tuned in fifths. This avoids too long a finger stretch (known as an "extension"). Modern double basses are usually tuned (low to high) E-A-D-G. The lowest string is tuned to E (the same pitch as the lowest E on a modern piano, approximately 41 cycles per second), nearly three octaves below middle C); and the highest string is tuned to G, an octave and a fourth below middle C (approximately 98 cycles per second).

A variety of tunings and numbers of strings were used on a variety of confusingly-named instruments through the sixteenth to the early twentieth centuries, by which time the four-stringed tuning mentioned above became almost universal.

Much of the classical repertoire has notes that fall below the range of a standard double bass. Notes below low E appear regularly in double bass parts in the Baroque and Classical eras, when the double bass was typically doubling the cello part an octave below. In the Romantic era and the 20th-century, composers such as Mahler, Beethoven, and Prokofiev also requested notes below the low E.

below There are two common methods for making these notes available to the player. Major European orchestras generally use basses with a fifth string, tuned to B three octaves and a semitonemiddle C.

In the United States, Canada and United Kingdom, most professional orchestral players use four-string double basses with an "C extension" which extends the lowest string down as far as low C, an octave below the lowest note on the cello (more rarely, this string may be tuned to a low B). The extension is an extra section of fingerboard mounted up over the head of the bass, which requires the player to reach back over the pegs to play, or to use a mechanical lever system.

A small number of bass players tune their strings in fifths, like a cello but an octave lower (C-G-D-A low to high). This tuning was used by the jazz player Red Mitchell and is increasingly used by classical players, notably the Canadian bassist Joel Quarrington. Tuning in fifths can also make the instrument louder, because the strings have more common overtones, causing the strings to vibrate sympathetically.^[8]

In classical solo playing the double bass is usually tuned a whole tone higher (F♯-B-E-A). This higher tuning is called "solo tuning," whereas the regular tuning is known as "orchestral tuning." String tension differs so much between solo and orchestral tuning that a different set of strings is often employed that has a lighter gauge. Strings are always labelled for either solo or orchestral tuning, and published solo music is arranged for either solo or orchestral tuning. Some popular solos and concerti, such as the Koussevitsky Concerto are available in both solo and orchestral tuning arrangements.

A variant and much less-commonly used form of solo tuning used in some Eastern European countries is (A-D-G-C), which uses three of the strings from orchestral tuning (A-D-G) and then adds a high "C" string. Some bassists with five string basses use a high "C" string as the fifth string, instead of a low "B" string. Adding the high "C" string facilitates the performance of solo repertoire with a high tessitura (range).

Playing and performance problems

Double bassists have the option to either stand or sit while playing the instrument. When standing, the double bass' height is set (by adjusting the endpin) so that the player may easily place the right hand close to the bridge, either with the bow (arco) or plucking (pizzicato). While personal opinions vary, often the endpin is set by aligning the first finger in either first or half position with the player's eye level. While sitting, a stool (which is measured by the player's seam length) is used. Traditionally, standing has been preferred by soloists although many now choose to play sitting down.

When playing in the upper register of the instrument (above the G below middle C), the player shifts his hand out from behind the neck and flattens it out, using the side of his thumb as a finger. This technique is called thumb position and is also a technique used on the cello. While playing in thumb position, the use of the fourth finger is replaced by the third finger, as the fourth finger becomes too short to produce a reliable tone.

Despite the size of the instrument, it does not project a loud volume, because its range is so low. When the bass is being used as an ensemble instrument in orchestra, usually between four and eight bassists will play the part in unison. In jazz and blues settings, the bass is normally amplified with a bass amplifier and loudspeakers. When writing solo passages for the bass, composers typically ensure that the orchestration is light, so it will not cover the bass.

Performing on the bass can be physically taxing because the strings of the bass are larger and thicker than those of a smaller stringed instrument. As well, since the bass is much larger than other stringed instruments, the space between notes on the fingerboard is larger. As a result, bass parts have relatively fewer fast passages, double stops, or large jumps in range. The increased use of playing techniques such as thumb position and modifications to the bass such as the use of lighter-gauge strings have reduced this problem to some degree.

As with all unfretted string instruments, performers must learn to place their fingers precisely to obtain the correct pitch. Because the bass is larger than other string instruments, the positions for the fingers are much further apart. As a result, more shifting of position is required, which increases the likelihood of intonation errors. As well, for bassists with smaller hands, the large spaces between pitches on the bass fingerboard may present a challenge, especially in the lower range, where the spaces between notes are largest.

Until the 1990s, child-sized double basses were not widely available, and the large size of the bass meant that children were not able to start the bass until their hand size and height would allow them to play a 3/4-size instrument (the most commonly-available size). In the 1990s and 2000s, smaller half, quarter, eighth and even sixteenth-sized instruments became more widely available, which meant that children could start at a younger age.

The double bass's large size, combined with the fragility of the wooden top and sides and the wood make safely transporting the instrument difficult. Since hard cases are both expensive and heavy, many bassists use soft cases. Some players use wheeled carts or endpin-attached