Take this short bit of music in G major that could be from a reel or hornpipe:
Let’s say you’ve started playing at a session and everyone plays this tune, but in A major.
If you want to join in, you need to transpose it up by two semitones. A semitone is a step from one note to another, adjacent note. The step from E to F is a semitone, as is F to F sharp, or G to G flat.
A quick note here about notes that have two names, or enharmonic equivalents. Every sharp/flat note has two names. For example, the note between F and G can be called F# (F sharp) or Gb (G flat). The reason why one name is used instead of another depends on the musical context.
F# is said to be the enharmonic equivalent of Gb. G# is the enharmonic equivalent on Ab, and so on. Here are all the enharmonic equivalents.
The chart below shows all enharmonic equivalents:
Enharmonic Equivalents
Look at the transposing chart below. Each column represents a semitone.
Now, using this chart, we’ll go back to transposing the excerpt of music above.
Locate the starting note of the music (G) in column 0. Count two columns to the right (moving up) you’ll get A (two semitones higher). When transposing up (i.e. making the tune higher in pitch) start on column 0.
The next note in example 1 is A. Find A in column 0 and count two steps to the right to find B.
The next note is B. Two steps to the right of B in column 0 will give you C#.
There was a choice here of using C# or its enharmonic equivalent, Db. Put simply, we choose C# to reduce confusion (although it may not seem like it!). If we chose Db, you’d have to put a lot of accidentals in the music because the music also has D naturals (D§). The same problem is faced in this example with making the choice between G# or Ab. There are A§ notes in the tune, so it makes sense to choose G# to avoid adding too many accidentals. If we’d gone with Ab and Db, example two would have looked like this:
Not a pretty sight!
So, all notes in the tune will be changed…
- From G to A
- From A to B
- From B to C sharp
- From C to D
- From D to E
- From E to F sharp (theoretically, as there are no E notes in this example)
- From F sharp to G sharp
…and you will end up with the following music:
This melody has been transposed from G major to A major!
See my next post on transposing down.