In music of the
common practice period, the tonic center was the most important of all the different tone centers which a composer used in a piece of music, with most pieces beginning and ending on the tonic, usually modulating to the dominant (the fifth scale degree above the tonic, or the fourth below it) in between. Two
parallel keys have the same tonic. For example, in both C major and C minor, the tonic is C. However,
relative keys (two different scales that share the same
key signature) have different tonics. For example, C major and A minor share a key signature that features no sharps or flats, despite having different tonic pitches (C and A, respectively). {{Image frame|content= { \relative c' { \clef treble \time 9/8 \key e \major \set Score.tempoHideNote = ##t \tempo "Très modéré" 4. = 36 \override Score.SpacingSpanner #'common-shortest-duration = #(ly:make-moment 1 8) \set Staff.midiInstrument = "flute" \stemDown cis'4.~(^"Flute"\p cis8~_\markup \italic "doux et expressif" cis16 \set stemRightBeamCount = #1 b \times 2/3 { \set stemLeftBeamCount = #1 ais16 a gis } g8. a16 b bis) cis4.~( cis8~ cis16 \set stemRightBeamCount = #1 b \times 2/3 { \set stemLeftBeamCount = #1 ais16 a gis } g8. a16 b bis) \override DynamicLineSpanner.staff-padding = #3 } } |width=430|caption=The
theme that opens
Claude Debussy's }}The term
tonic may be reserved exclusively for use in tonal contexts while
tonal center or
pitch center may be used in post-tonal and
atonal music: "For purposes of non-tonal centric music, it might be a good idea to have the term 'tone center' refer to the more general class of which 'tonics' (or tone centers in tonal contexts) could be regarded as a subclass." Thus, a pitch center may function referentially or contextually in an atonal context, often acting as an
axis or line of symmetry in an
interval cycle. The term
pitch centricity was coined by
Arthur Berger in his "Problems of Pitch Organization in Stravinsky". According to
Walter Piston, "the idea of a unified classical tonality replaced by nonclassical (in this case nondominant) centricity in a composition is perfectly demonstrated by
Debussy's ''
Prélude à l'après-midi d'un faune''". The tonic includes four separate activities or roles as the principal goal tone, initiating event, generator of other tones, and the stable center neutralizing the tension between dominant and subdominant. The tonic chord is said to have tonic
function where the tension is at its lowest and the chord progression is resolved, alongside other chords such as the
submediant (vi) chord. ==See also==