Bass (sound)
Bass (/beɪs/ BAYSS) (also called bottom end)[2] describes tones of low (also called "deep") frequency, pitch and range from 16 to 250 Hz (C0 to middle C4)[3] and bass instruments that produce tones in the low-pitched range C2-C4. They belong to different families of instruments and can cover a wide range of musical roles. Since producing low pitches usually requires a long air column or string, and for stringed instruments, a large hollow body, the string and wind bass instruments are usually the largest instruments in their families or instrument classes.
Kinds of bass harmony[edit]
In classical music, different forms of bass are: basso concertante, or basso recitante; the bass voice of the chorus; the bass which accompanies the softer passages of a composition, as well as those passages which employ the whole power of the ensemble, generally played by the violoncellos in orchestral music; contrabass (“under bass”), is described as that part which is performed by the double basses; violoncellos often play the same line an octave higher, or a different melodic or rhythmic part which is not a bassline when double basses are used; basso ripieno; that bass which joins in the full passages of a composition, and, by its depth of tone and energy of stroke, affords a powerful contrast to the lighter and softer passages or movements.[4]
Basso continuo was an approach to writing music during the Baroque music era (1600-1750). With basso continuo, a written-out bassline served to set out the chord progression for an entire piece (symphony, concerto, Mass, or other work), with the bassline being played by pipe organ or harpsichord and the chords being improvised by players of chordal instruments (theorbo, lute, harpsichord, etc.).
"The bass differs from other voices because of the particular role it plays in supporting and defining harmonic motion. It does so at levels ranging from immediate, chord-by-chord events to the larger harmonic organization of an entire work."[5]
Movies[edit]
The use of subwoofers to provide deep bass in film presentations received a great deal of publicity in 1974 with the movie Earthquake which was released in Sensurround. Initially installed in 17 U.S. theaters, the Cerwin Vega "Sensurround" system used large subwoofers which were driven by racks of 500 watt amplifiers which were triggered by control tones printed on one of the audio tracks on the film. Four of the subwoofers were positioned in front of the audience under (or behind) the film screen and two more were placed together at the rear of the audience on a platform. Powerful noise energy and loud rumbling in the range of 17 Hz to 120 Hz was generated at the level of 110–120 decibels of sound pressure level, abbreviated dB(SPL). The new low frequency entertainment method helped the film become a box office success. More Sensurround systems were assembled and installed. By 1976 there were almost 300 Sensurround systems leapfrogging through select theaters. Other films to use the effect include Midway in 1976 and Rollercoaster in 1977.[24]
