Definition: A sequence of notes or chords comprising the close of a musical phrase.
Perfect Cadence: When a Dominant or Dominant 7th Chord is played followed by Tonic Chord.It is a way of finishing off a musical phrase or structure in a nice rounded way. It is also known as finishing cadence by moving from Vth to the Ist (tonic).Used in finishing rounding Classical Orchestral Compositions by repetitive use.
Plagal Cadence:When a Sub-dominant or Sub-dominant 7th Chord is played followed by Tonic Chord.It is a way of finishing off a musical phrase or structure in a nice rounded, complete way. It is also known as an “Amen” Cadence which gives a softer finishing.It is used mostly in Gospel or Blues. Also known as finishing cadence by moving from IVth to the Ist (tonic).
Imperfect Cadence (Half Cadence): When a Chord is played followed by Dominant (5th) Chord. It is a way of progressing in a musical phrase or structure where is it just short of the feeling of completion.open or imperfect cadence is the one which always ends on the dominant chord and which can be approached from any other chord, the most common being I, II, IV or VI. It can be formed by following movements.I – V, ii – V, IV – V, VI – V. It is also known as a half cadence.
Interrupted Cadence (Deceptive Cadence): In music, a cadence that does not end with the expected chord of the tonic but moves from the dominant to the submediant or subdominant.It is a way of progressing in a musical phrase or structure where it sets up expecting one thing and in fact interrupts that thing to give us something else.The expectation that a dominant chord moves to a tonic chord, thus producing a perfect cadence, is very strong. For this reason, if a dominant chord is followed by any other chord, the feeling is one of 'interruption'. So an interrupted cadence is a dominant chord followed by any chord except the tonic. Deceptive cadence is where the Dominant resolves to a chord from the tonic family. Interrupted cadence is where the second chord has no relation to the tonic family.
Example: Instead of naturally moving from V – I (Perfect cadence), it unexpectedly moves to vi and gives V – vi, V – IV is also one of the examples of this cadence.