Know your key signatures. What key is the original piece in? How far do you need to transpose it? What will the new key be? Once you have figured out your new key, stick to it, even if it seems like a tricky one. Don’t jumble sharps and flats: a sequence of E, F sharp, G sharp up a tone is F sharp, G sharp, A sharp (NOT B flat).
Know your intervals. Visualise how far a note needs to move up or down the stave. Is the original note on a line or in a space? What about the new one? If transposing up or down a tone, a note in a space will move to a line and vice versa; if going up or down a third, you’ll just move to the next line or space.
Identify shapes and patterns. Most pieces are made up of fragments of scales and arpeggios. Learn the scale and arpeggio in the new key and play the scale sections you have identified separately, before attempting the piece as a whole. Try to be aware of the degrees of the scale – what is the new tonic, mediant and dominant? Try not to transpose note by note, but think in sequences of notes, following the contours of the melody.
Learn common chord-progressions. Keyboard players can learn simple chord-progressions, starting with II-V-I cadences in different keys. Try transposing the chords from a simple pop song – this will help to develop an understanding of harmonic relationships in different keys.
Beware of accidentals. Consider the effect of an accidental: it will change the note up or down a semitone, momentarily contradicting the key signature. But a sharp will not necessarily become a sharp in the new key. Suppose a piece in C major has an F sharp accidental. Transpose it up a fifth, this will become C sharp in G major, but up a fourth will become B natural in F major. Similarly, a flat may become a flat or natural in the new key. Occasionally, you might encounter a double sharp – E sharp up a tone is F double sharp. It’s important to maintain the integrity of the key and not call it G.
Don’t confuse the key of an instrument with the key of a piece. The key of the instrument will dictate the interval by which you need to transpose, but is not relevant to the key of the actual music. For example, a trumpet is pitched in B flat. If a trumpeter is asked to play a horn in F part, the distance from B flat to F is down a fourth. This will be the distance to transpose both the key signature and the notes. If the original music is written in D major, you’ll be playing down a fourth in A major.
Read in different clefs. Let’s suppose a violinist wants to play an E flat saxophone part written in C major (transposing concert pitch to E flat). Treble clef C is in the same position on the stave as a bass clef E, so they could read it in the bass clef, but must remember to transpose the key signature to E flat major: treble clef C becomes bass clef E flat. But beware of any accidentals, as previously mentioned; octaves also need to be adjusted.
Transpose by ear as well as from notation. This helps to develop instinctive playing without overthinking. Try playing simple tunes such as ‘Happy Birthday’ or ‘Twinkle, Twinkle, Little Star’ in different keys without the music. This is also a great way to consolidate scales you might be learning.
Use untransposed parts. Avoid writing out transposed parts. With practice, pupils will soon develop their transposition superpowers, even if they struggle at first. As well as improving their knowledge of music theory, they may become invaluable ensemble members if able to cover missing parts in different keys at a moment’s notice.
Just have a go! You don’t have to be an advanced player and you don’t have to play a ‘transposing’ instrument. It’s a great way for siblings and friends to play together, even if they play instruments in different keys, or to accompany vocalists who need to change the key of a song to suit their vocal range.
