Consonance and dissonance

Within the Western tradition, some listeners associate consonance with sweetness, pleasantness, and acceptability, and dissonance with harshness, unpleasantness, or unacceptability, although there is broad acknowledgement that this depends also on familiarity and musical expertise.

Other musical styles such as Bosnian ganga singing, pieces exploring the buzzing sound of the Indian tambura drone, stylized improvisations on the Middle Eastern mijwiz, or Indonesian gamelan consider this sound an attractive part of the musical timbre and go to great lengths to create instruments that produce this slight "roughness".

[19] Sensory dissonance and its two perceptual manifestations (beating and roughness) are both closely related to a sound signal's amplitude fluctuations.

"[30] In human hearing, the varying effect of simple ratios may be perceived by one of these mechanisms: Generally, the sonance (i.e., a continuum with pure consonance at one end and pure dissonance at the other) of any given interval can be controlled by adjusting the timbre in which it is played, thereby aligning its partials with the current tuning's notes (or vice versa).

([38][15] Controlling the sonance of pseudo-harmonic timbres played in pseudo-just tunings in real time is an aspect of dynamic tonality.

This contrasts with violins, flutes, or drums, where the vibrating medium is a light, supple string, column of air, or membrane.

The overtones of the inharmonic series produced by such instruments may differ greatly from that of the rest of the orchestra, and the consonance or dissonance of the harmonic intervals as well.

[40] According to John Gouwens,[40] the carillon's harmony profile is summarized: When we consider musical works we find that the triad is ever-present and that the interpolated dissonances have no other purpose than to effect the continuous variation of the triad.Dissonance has been understood and heard differently in different musical traditions, cultures, styles, and time periods.

[43] Various psychological principles constructed through the audience's general conception of tonal fluidity determine how a listener will distinguish an instance of dissonance within a musical composition.

Based on one's developed conception of the general tonal fusion within the piece, an unexpected tone played slightly variant to the overall schema will generate a psychological need for resolve.

Dissonance is the harsh and unhappy percussion (aspera atque iniocunda percussio) of two sounds mixed together (sibimet permixtorum)".

In the common practice period, musical style required preparation for all dissonances,[citation needed] followed by a resolution to a consonance.

At the end of the St Matthew Passion, where the agony of Christ's betrayal and crucifixion is portrayed, John Eliot Gardiner[58] hears that "a final reminder of this comes in the unexpected and almost excruciating dissonance Bach inserts over the very last chord: the melody instruments insist on B natural—the jarring leading tone—before eventually melting in a C minor cadence."

[59] Gillies Whittaker[60] points out that "The thirty-two continuo quavers of the initial four bars support four consonances only, all the rest are dissonances, twelve of them being chords containing five different notes.

Benedictus on YouTube from Michael Haydn's Missa Quadragesimalis, MH 552 performed by Purcell Choir and Orfeo Orchestra conducted by György Vashegyi Mozart's music contains a number of quite radical experiments in dissonance.

An even more famous example from Mozart comes in a magical passage from the slow movement of his popular "Elvira Madigan" Piano Concerto 21, K467, where the subtle, but quite explicit dissonances on the first beats of each bar are enhanced by exquisite orchestration:Philip Radcliffe[62] speaks of this as "a remarkably poignant passage with surprisingly sharp dissonances".

Radcliffe says that the dissonances here "have a vivid foretaste of Schumann and the way they gently melt into the major key is equally prophetic of Schubert."

When this passage returns later in the same movement (just before the voices enter) the sound is further complicated with the addition of a diminished seventh chord, creating, in Scruton's words "the most atrocious dissonance that Beethoven ever wrote, a first inversion D-minor triad containing all the notes of the D minor harmonic scale": Robert Schumann's song "Auf einer Burg" from his cycle Liederkreis, Op.

In the scene known as "Hagen's Watch" from the first act of Götterdämmerung, according to Scruton[66] the music conveys a sense of "matchless brooding evil", and the excruciating dissonance in bars 9–10 below it constitute "a semitonal wail of desolation".

These new resources provide musicians with an alternative to pursuing the musical uses of ever-higher partials of harmonic timbres and, in some people's minds, may resolve what Arnold Schoenberg described as the "crisis of tonality".

([71] George Russell, in his 1953 Lydian Chromatic Concept of Tonal Organization, presents a slightly different view from classical practice, one widely taken up in Jazz.

Russell extends by approximation the virtual merits of harmonic consonance to the 12TET tuning system of Jazz and the 12-note octave of the piano, granting consonance to the sharp eleventh note (approximating the harmonic eleventh), that accidental being the sole pitch difference between the major scale and the Lydian mode.

Dan Haerle, in his 1980 The Jazz Language,[73] extends the same idea of harmonic consonance and intact octave displacement to alter Paul Hindemith's Series 2 gradation table from The Craft of Musical Composition.

For context: unstated in these theories is that musicians of the Romantic Era had effectively promoted the major ninth and minor seventh to a legitimacy of harmonic consonance as well, in their fabrics of 4-note chords.