Compound Intervals - Salford Piano Studio

A Compound interval is any interval larger than an octave.

Let’s have a look at a 9th.

We can think of this 9th in two ways:

A Simple 9th
A Compound 2nd

A 2nd and a 9th consist of the same note, only an octave higher.

a simple second interval from C to D on the treble staff, next to a compound second interval from C to D

Here it is on the piano:

a piano keyboard how to play a simple second and a compound second

Note: Compound intervals are identical to simple intervals in terms of their interval quality.

Let’s start with a simple interval this time.

This is a Major 3rd:

a simple third interval from C to E on the treble staff

A Compound Major 3rd is also a Simple Major 10th

a simple third interval from C to E on the treble staff, next to a compound third interval from C to E

As always, it’s useful to see it on the piano:

a piano keyboard how to play a simple third and a compound third

Simple Vs. Compound Intervals

We usually write simple intervals up to 13th, that is a Compound 6th.

Use this as a guide:

Compound 2nd – Simple 9th
Compound 3rd – Simple 10th
Compound 4th – Simple 11th
Compound 5th – Simple 12th
Compound 6th – Simple 13th

a chart contrasting simple and compound intervals from a simple ninth to a simple thirteenth

Example

The Finale from Beethoven’s Piano Trio no. 1 starts with a Compound 3rd (a Simple 10th). He then fills that gap with descending E Flat Major notes.

Excerpt: Beethoven Piano Trio In E Flat Major, Op. 1 No. 1, 4th mv.