The omnibus progression in music is a chord progression

Chord progression

A chord progression is a series of musical chords, or chord changes that "aims for a definite goal" of establishing a tonality founded on a key, root or tonic chord. In other words, the succession of root relationships...

 characterized by chromatic lines moving in opposite directions. The progression has its origins in the various Baroque harmonizations of the descending chromatic fourth

Chromatic fourth

In music, a chromatic fourth, or passus duriusculus, is a melody or melodic fragment spanning a perfect fourth with all or almost all chromatic intervals filled in . The quintessential example is in D minor with the tonic and dominant notes as boundaries, :The chromatic fourth was first used in the...

 in the bass ostinato pattern of passacaglia

Passacaglia

The passacaglia is a musical form that originated in early seventeenth-century Spain and is still used by contemporary composers. It is usually of a serious character and is often, but not always, based on a bass-ostinato and written in triple metre....

, known as the "lament bass

Lament bass

In music, the lament bass is a ground bass, built from a descending perfect fourth from tonic to dominant, with each step harmonized. The diatonic version is the upper tetrachord from the natural minor scale, known as the Phrygian tetrachord, while the chromatic version, the chromatic fourth, has...

". However, in its fullest form the omnibus progression involves a descent in the bass

Bass (voice type)

A bass is a type of male singing voice and possesses the lowest vocal range of all voice types. According to The New Grove Dictionary of Opera, a bass is typically classified as having a range extending from around the second E below middle C to the E above middle C...

 which traverses a whole octave

Octave

In music, an octave is the interval between one musical pitch and another with half or double its frequency. The octave relationship is a natural phenomenon that has been referred to as the "basic miracle of music", the use of which is "common in most musical systems"...

 and includes every note of the chromatic scale

Chromatic scale

The chromatic scale is a musical scale with twelve pitches, each a semitone apart. On a modern piano or other equal-tempered instrument, all the half steps are the same size...

. It may also include one or more chromatic ascending tetrachord

Tetrachord

Traditionally, a tetrachord is a series of three intervals filling in the interval of a perfect fourth, a 4:3 frequency proportion. In modern usage a tetrachord is any four-note segment of a scale or tone row. The term tetrachord derives from ancient Greek music theory...

s in the soprano

Soprano

A soprano is a voice type with a vocal range from approximately middle C to "high A" in choral music, or to "soprano C" or higher in operatic music. In four-part chorale style harmony, the soprano takes the highest part, which usually encompasses the melody...

, tenor

Tenor

The tenor is a type of male singing voice and is the highest male voice within the modal register. The typical tenor voice lies between C3, the C one octave below middle C, to the A above middle C in choral music, and up to high C in solo work. The low extreme for tenors is roughly B2...

 and alto

Alto

Alto is a musical term, derived from the Latin word altus, meaning "high" in Italian, that has several possible interpretations.When designating instruments, "alto" frequently refers to a member of an instrumental family that has the second highest range, below that of the treble or soprano. Hence,...

. They are also known as "chromatic wedge progressions", in reference to their wedge-like appearance in score. The origin of the term "omnibus" (Latin: "for all") to describe such a sequence is unclear.

A simple example

The following example is in C major. The lowest part is a "lament bass" that descends from the tonic

Tonic (music)

In music, the tonic is the first scale degree of the diatonic scale and the tonal center or final resolution tone. The triad formed on the tonic note, the tonic chord, is thus the most significant chord...

 to the dominant

Dominant (music)

In music, the dominant is the fifth scale degree of the diatonic scale, called "dominant" because it is next in importance to the tonic,and a dominant chord is any chord built upon that pitch, using the notes of the same diatonic scale...

 using chromatic passing tones before returning at the end up to the tonic in a perfect cadence. The upper voice moves in the opposite direction from the dominant note up to the tonic. The chord names are given, followed where necessary by the inversion

Inversion (music)

In music theory, the word inversion has several meanings. There are inverted chords, inverted melodies, inverted intervals, and inverted voices...

 in figured bass

Figured bass

Figured bass, or thoroughbass, is a kind of integer musical notation used to indicate intervals, chords, and non-chord tones, in relation to a bass note...

. For example, 'Cm(6/4)' refers to a C minor triad in second inversion.

| C | G7(6/5) | Bb7 | Dm(6/4) | Bb7(4/2) | G7 | C |

A more extended treatment of this version of the omnibus could be:

| C | G7(6/5) | Bb7 | Dm(6/4)| Bb7(4/2)| G7 | Bm(6/4)| G7(4/2)|
| E7 | G#m(6/4)| E7(4/2)| C#7 | Fm(6/4) | C#7(4/2)| Bb7 | Dm(6/4)| Bb7(4/2) | G7 | C |

For the purposes of composition

Musical composition

Musical composition can refer to an original piece of music, the structure of a musical piece, or the process of creating a new piece of music. People who practice composition are called composers.- Musical compositions :...

, the pattern may be halted at any point, and in so doing may facilitate modulation

Modulation (music)

In music, modulation is most commonly the act or process of changing from one key to another. This may or may not be accompanied by a change in key signature. Modulations articulate or create the structure or form of many pieces, as well as add interest...

 to any desired key

Key (music)

In music theory, the term key is used in many different and sometimes contradictory ways. A common use is to speak of music as being "in" a specific key, such as in the key of C major or in the key of F-sharp. Sometimes the terms "major" or "minor" are appended, as in the key of A minor or in the...

.

Dominant prolongation

Modern theorists such as Telesco explain how small sections of omnibus progression (signified in example 1 by brackets around groups of chords) can be viewed as an instance of dominant prolongation

Prolongation

In music theory, prolongation refers to the process in tonal music through which a pitch, interval, or consonant triad is able to govern spans of music when not physically sounding...

 achieved through voice exchange

Voice exchange

In music, especially Schenkerian analysis, a voice exchange is the repetition of a contrapuntal passage with the voices' parts exchanged; for instance, the melody of one part appears in a second part and vice versa...

. Example 2 (above) is effectively a prolongation of the dominant seventh chord G7 which utilises chromatic voice movement. The bass voice descends chromatically while the upper voice ascends chromatically, and the inner voices remain stationary on the notes of D and F. Eventually the chromatic movement results in a new inversion of the dominant seventh chord G7, resolving to the tonic chord C.

Examples

Examples from the classical reportoire include Schubert

Franz Schubert

Franz Peter Schubert was an Austrian composer.Although he died at an early age, Schubert was tremendously prolific. He wrote some 600 Lieder, nine symphonies , liturgical music, operas, some incidental music, and a large body of chamber and solo piano music...

's Piano Sonata in A minor, Op. 42, first movement, mm. 32-39, and Brahms

Johannes Brahms

Johannes Brahms was a German composer and pianist, and one of the leading musicians of the Romantic period. Born in Hamburg, Brahms spent much of his professional life in Vienna, Austria, where he was a leader of the musical scene...

' Opus 116, No. 3.

Further reading

• Kostka, Stefan, and Dorothy Payne. Tonal Harmony. 6th edition. New York: McGraw-Hill, 2009. (Pp. 476-480)
• Laitz, Steven G. The Complete Musician. 2nd edition. New York: Oxford University Press, 2008. (Pp. 845-846)

External links

• Examples of the Omnibus, compiled by Prof. Timothy Cutler