How to Transpose Up a Perfect 5th

By now you should be feeling very confident transposing between all four clefs, up and down an octave and also up and down a major second! Now we need to learn how to transpose up a perfect 5th!

Which instruments do we have to think about when transposing a perfect 5^th?

The most common instrument we think about when transposing a perfect 5^th is the French horn! This is because when the French horn plays a C we actually hear a G. 

But firstly…Why is the 5^th called perfect?

Remember with the intervals of a 5^th, 4^th and octave we don’t use the descriptive words, ‘major’ or ‘minor’. 

This is because these interval’s do not vary whether they are in the major or minor scales. This means that they only have one ‘normal’ state which is perfect!

Let’s have a look if we write out the C major scale below:

And then write out the C minor scale…

What do you notice about the 4^th, 5^th and 8^th notes in both of these scales?

They are the same!

Let’s also look at the F scales… here is the F major scale:

Here is the F minor scale. 

What do you notice? That’s right, the 4^th 5^th and 8^th notes are the same!

Now back to the interval of a 5^th….

Remember we said that we use the transposition of a perfect 5^th when we think about the French horn. This is because when the French horn sees a C, we hear a G. 

Let’s think about that…

We see a C

We hear a G

Let’s write out the C major scale… What is the 5th note?

That’s correct it’s G!

As you read earlier, the 5^th only has one normal state and that is perfect, so we know that this is a perfect 5^th already. So in order to write out the sounding pitch (the note we hear), we must transpose up a perfect 5th.

Now we are clear with that.. Here is a short melody in C major

We have already worked out that if we transpose a C up a perfect 5th we get a G. This means that we now need to put the key signature of G major at the start of our melody. 

The key signature of G major has one sharp.

• If you are still unclear on your key signatures, please make sure you are familiar with your circle of fifths. 

Once you have changed your key signature, we then need to follow this with transposing all the notes in the melody up a perfect 5th.

Let’s try another example

What key is our melody in below?

That’s correct, we are in A major!

Can you transpose up a perfect 5th from A?

The fifth note above A is E. This means we now need the key signature of E major. How many sharps does E major have? 4!

Once you have changed the key signature, simply move all of your notes up a 5^th. 

Notice that the interval of a 5^th matches perfectly with our Circle of fifths!

Clue’s in the name….

What about accidentals?

This is very simple if you have seen the previous blog posts. 

Remember when we are presented with an interval, we work out the descriptive word by asking ourselves, is the top note in the scale of the bottom note? 

So if we have the below interval…

We can clearly see that this is a 5^th … but how do we check that this is a perfect 5^th?

We ask ourselves:

Is our top note in the scale of our bottom note?

Or

Is D in G major?

The answer would be yes!

Let’s now add an accidental in:

Is Bb in Eb major?

It absolutely is, so this is a perfect 5^th. 

If we had been presented with a B natural then you would need to add in a flat sign in order to make it a perfect 5^th. 

You must always pay attention to your accidentals and treat these separately.

I hope that has given you a clear overview of how to transpose up a perfect fifth! 

Check out my other blog posts here!