Piano arpeggios: from chords to accompaniment

A block chord is a chord whose notes are struck together. An arpeggio plays the same notes one after the other. Nothing changes in the harmony: you still hear C, E and G, the C chord. What changes is the motion. A block chord marks a moment; an arpeggio fills the time until the next chord.

Listen to the three versions. In the last one, each note keeps sounding while the next ones arrive, and the chord builds up note by note. Fingers 1, 3 and 5 on C, E and G are a common suggestion for the right hand.

With the same three notes you can draw many shapes. Going up, C E G C, is the most direct. Going up and down makes a wave that loops back on itself. The pattern 1-5-3-5 counts the chord’s notes from the root: root, fifth, third, fifth, so C G E G. It stays in one hand position and keeps a steady motion.

The last one, 1-5-8-10, belongs to the left hand: root, fifth, octave, then the tenth, which is the third one octave higher. It spans more than an octave, so it opens the hand wide; if that is uncomfortable, stop at 1-5-8 and come back down. Watch the keys light up as they sound, then lower the tempo and play along.

An arpeggio becomes an accompaniment as soon as it follows a few chords. Here the loop alternates C and Am, two bars each. The pattern keeps its shape and simply moves onto the notes of the new chord: A C E A for “up”, A E C E for 1-5-3-5, A E A C for 1-5-8-10.

The two chords share two notes, C and E, so the hand hardly moves. That is no accident: chords that share notes are easy to link, a point the guide on changing chords smoothly develops. In this loop each note rings a little longer than its beat, as if you kept the keys down: the arpeggio sounds like a chord again.

Try one pattern over the four chords of your first chord progression, or under a tune with the left-hand patterns.