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How to Practice the "Moonlight" Sonata


Question: Albert,

I am very impressed with this website. It is sure to help many people as it has helped myself. I am going to be playing the “Moonlight” Sonata in 22 days at my high school for a talent show and I would like to know an efficient way to practice it – aspects such as how might time I should spend each day on it.

Also, I have recognized that it is to be played in a C# minor chord. I have no idea what a chord really is; literally, all I know about it is that it is just some long list of notes on a staff and if they are sharps or flats. Could you clarify what a chord is?


– Caleb (Bellevue, Washington, USA)

Albert’s reply: Chords make up the entire essence of the “Moonlight” Sonata. (I assume you’re referring to the first movement, although this also applies to the virtuosic third movement.)

For starters, make sure you don’t confuse chords with keys. Let me explain the difference. I’ll get somewhat technical here, but don’t worry since I’ll clarify all the details step by step – then I’ll show you the most effective way to practice the “Moonlight” Sonata based on what you’ve learned about chords.

What’s the Difference Between a Chord and a Key?

A chord is three or more notes that belong together harmonically. A key is the harmonic basis for a set of chords. In other words, each key has a set of chords associated with it – chords that the ear comes to expect.

A chord can be described either absolutely or relatively. The description “C-sharp minor chord” (also called C-sharp minor triad) is an absolute description of this chord. It refers to the notes C-sharp, E and G-sharp (just like in the first measure of the “Moonlight” Sonata). When you refer to the C-sharp minor chord, you’re not simultaneously referring to or even implying a key. You’re referring only to the notes C-sharp, E and G-sharp sounding together as a chord, no matter what key the music happens to be in. (The music might even be atonal – without any key at all – yet these notes can still sound together as a chord.)

The “Moonlight” Sonata happens to be in the key of C-sharp minor. This means that the key (also called the tonality) is built on the note C-sharp. This note is called the tonic – the first note of a key. The key is built on the notes C-sharp, D-sharp, E, F-sharp, G-sharp, A and B. If you play them in this order, you will have played a C-sharp natural minor scale. In other words, the key consists of the notes of the scale.

The tonic chord in the key of C-sharp minor is the C-sharp minor triad. Here, the notes C-sharp, E and G-sharp are the first, third and fifth notes of the C-sharp minor scale, also called scale degrees 1, 3 and 5:

(The standard notation for scale degrees is a number with a caret sign (^) above it.)

In this case, since we’ve defined a key (C-sharp minor), we can make a relative reference to the tonic chord. We do so simply by referring to the scale degree on which the chord is built. Since the tonic chord is built on scale degree 1 (the first note of the scale), we call this the i chord (pronounced “one chord”). A lowercase “i” is used because the quality of this chord is minor (it’s called a C-sharp minor chord, after all). For major chords, uppercase Roman numerals are used.

This chord can be used in other keys. If the music were in the key of G-sharp minor, for example, the notes C-sharp, E and G-sharp still appear in that key. This time, however, they are scale degrees 4, 6 and 1, respectively:

If a C-sharp minor chord were used in the key of G-sharp minor, it would be referred to relatively as a iv chord (pronounced “four chord”) because it is built on the fourth note of the G-sharp minor scale. In other words, C-sharp is scale degree 4 in the scale of G-sharp minor, so the C-sharp minor chord is a iv chord (lowercase because the chord is minor, and iv because it’s built on scale degree 4).

Can you see that this is actually easier than it appears at first glance?

How to Practice the “Moonlight” Sonata

This leads us back to the “Moonlight” Sonata. Now that you understand what a chord is, you should be able to recognize them in the music you play. In the case of the “Moonlight” Sonata, the most effective practice strategy for learning the piece (especially for memorizing it) is to practice block chords:

That is, instead of always practicing the arpeggios written by Beethoven, in which the notes of the chord are played one at a time, play the chords that the groups of notes form.

You should at least know the absolute chord names in the music you play, even if you don’t always understand their functions within the key. In this piece, the first chord, in measure 1, is a C-sharp minor chord. (We’ll ignore measure 2 because the B in the bass is what’s called a passing tone; it has no harmonic function and isn’t actually a part of the chord.)

Measure 3 contains an A major chord (A, C-sharp, E), and then a D major chord (D, F-sharp A). Note that the D major chord is inverted:

This means that the root of the chord (D – the note on which the chord is built) is not the bass (bottom) note. Instead, the next note, F-sharp, is the bass note, making this the first inversion. (See the lessons on chord inversions for more detail.)

By understanding the chords and practicing them in this way you will learn much faster!

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