How to Transpose Down a Major Second

By Jade Bultitude
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In the last blog post we looked at how to transpose up a major second! It is not a surprise then that this week we will be looking at how to transpose down a major second!

It is important to separate the two, going up and down. Although they seem very similar, they do require slightly different skills and we can often get the two confused. 

A few things to remember before we transpose down a major second

Before starting, we just need to remind ourselves why we have to transpose a major second at all – whether this be up or down! Transposing is used when we have an instrument that is ‘in a key’. 

What does ‘in a key’ mean?

This simply means that when the instrument plays a ‘C’ we will hear a different note. 

Remember, when the Clarinet in Bb plays a C we, as the audience, hear a Bb. 

middle C, treble clef
Middle C – the note the clarinet will see on the music. The written pitch.
B flat, below middle C, major second lower
Bb – The note we will hear. The sounding pitch.

When the saxophone in the key of Eb plays a C, we hear an Eb!

treble C, treble clef, written pitch
C – The note the saxophone will see on the music. The written pitch.
E flat, written pitch, major second lower
Eb – The note we will hear. The sounding pitch.

The reason we need to transpose could be for the following reasons:

  • The conductor needs to have all the instruments in sounding pitch so it is easier for them to understand the score and see the chords. 
  • A piece of music has been written only with the sounding pitch in mind and it needs to be written so that the instrument can play it properly. 

What did we learn in the last blog post?

Last time we specifically talked about transposing instruments in the key of Bb. Why?

Because Bb and C are a major second apart. 

How did we know that B flat and C are a major second apart?

Remind yourself with the piano below. 

piano, B flat, C natural, major second apart

We hear a Bb

We read a C

As you can see our sounding pitch is a major second BELOW our written pitch. Now, if you remember, in our last post we discussed transposing up a major second. This means we were transposing from sounding pitch to written pitch!

This week we will look at how to transpose effectively from written pitch to sounding pitch (the opposite way!)

Have a look at the last blog post to remind yourself WHY this is a MAJOR 2nd, if you are unclear. 

So how can I transpose down a major second?

Here is a simple melody in C major. 

C major, melody, short melody, treble clef

We need to transpose this down a major second in order for us to see what the sounding pitch of the melody is. 

We could look at each note individually but this would take us ages! The easiest thing to do is change the key signature first. But how do we work out what is a major second lower than C major?

Remember, a major second is the same as a TONE (2 semitones). 

So what is two semitones lower than C?

Take a look at the piano below…

piano, B flat, C natural, major second apart

That’s right – Bb is a tone lower than C. 

Now you can simply check that this is a major second by asking, is C natural in Bb major? (Remember we always work out an interval by asking: is the top note in the scale of the bottom note)

is in Bb major!

Now let’s go back to our short melody – 

We now need to change the key signature to a Bb major key signature. This will be two flats!

Once the key signature is changed we then need to move all of our notes down a second. 

B flat major melody, short melody, treble clef, major second lower
Answer, transpose down a major second, C major, B flat major
On the left we have our original melody – On the right we have the melody transposed down a major 2nd

Let’s try another example

The melody below is in A major (3 sharps). This is the written pitch. 

We need to transpose this down a major second so that we can see the sounding pitch. 

A major, short melody, melody

Now let’s transpose it so we can see what the sounding pitch is. 

What is a major second below A… Let’s look at our piano below

Piano, A natural

Remember to the left of the piano is lower, the right of the piano is higher!

What note is a tone (two semitones) lower than A?  Remember a tone is the same as a major 2nd!

It’s a G natural!

Piano, A natural, G natural, major second apart

We can check that this is right by asking ourselves… 

Is A natural in G major? (Is the higher note of my interval in the key of my lower note?)

Yes it is!

We now know that we will need a key signature of ONE sharp. This is because G major only has one sharp. Below is our new key signature. 

G major, key signature, G major key signature

We now need to move each note down by a second…

G major melody, major second lower, transposed, melody
Answer, A major melody, G major melody, transposed down a major second
On the left we have our original melody – On the right we have our melody transposed down a major 2nd

Let’s think about our accidentals…

If you see an accidental (sharp, flat or natural sign) in the original melody, these need to be treated differently. This is because they are not in the original key signature. Simply look at the note and find a major second below it (like we did with the key signature).

Remember that to find out if we have a MAJOR second we must ask ourselves if the top (higher) note is in the scale of the bottom note. 

Lets think about the note below…

treble clef, G sharp, semibreve

Now let’s look at our piano… 

piano, G sharp

Which note is a major second lower? Remember a tone (two semitones) is the same as a major second. 

piano, F sharp, G sharp, major second apart, major second

That’s correct, F sharp is a major second lower. 

Again, we can check. Is G sharp in F sharp major? – YES! 

If you are not completely sure of all of your scales just yet, then remember to use the handy interactive circle of fifths available on my website!

Have a great week and leave your comments below!

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Jade is an experienced musician and teacher as well as being the founder of Music Theory Foundations. She has been helping people learn music theory for more than 10 years from pre school children all the way to degree level studies.

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