Transposition at the Octave

If the notes of a melody are written each an octave higher or an octave lower, the melody is said to have been transposed up or down an octave. Transposing up or down one or more octaves is the simplest form of transposition because all the notes retain their original note names. Accidentals retain the same form and the key signature is unchanged, subject only to the modification necessary should one write the transposed melody in another clef.

The same melody is written on four lines. Each melody is one octave lower than that on the line above.

Transposition into another Key

A piece of music can be transposed up or down any interval, not only multiples of the octave. In such a case the key signature will change. We give examples below where the key signatures have not been changed and then, below, each line rewritten with the correct key signature.

These examples hide the most difficult aspect of transposition which is how to handle accidentals. Sometimes the accidental is changed and sometimes it is not. When we discussed the conventions of notating diatonic and chromatic scales we found that there we had to chose between a number of enharmonically equivalent ways of writing certain notes. Identical choices face us when transposing accidentals. The rule is that the intervals in the original melody will be preserved in the transposed form.

The examples below are in G and F minor respectively. Notice how in the first bar, the sharpened 7th in G minor, F sharp, becomes the sharpened 7th in F minor, E natural and how in the second bar, the sharpened 4th in G minor, C sharp, becomes the sharpened 4th in F minor, B natural - in each case the conventional notation for each key.

What Key is My Instrument in?

by the late John Howell

Totally ignoring clefs and transposed music, how do we decide what "key" a woodwind instrument is in?

The logical answer, it seems to me, is that we name the key of the instrument for the note produced with 7 fingers down. That certainly applies to recorders, to shawms and oboes of all sizes and periods, to all saxophones, and to all clarinets (as long as we specify that it's the 7-finger note in the upper register). It's irrelevant in speaking of the rankett or bassoon, because the part is always in bass clef, concert pitch, but in fact the modern bassoon and the bass curtal and baroque bassoon are in F (the 7-finger note) and indeed do use the equivalent of bass recorder fingering.

A number of instruments have extension keys to reach lower notes than the 7-finger one, but we don't change our terminology because of that.

But what if an instrument only has 6 finger holes? (I'm ignoring the thumbhole, which some instruments have and others don't.) The renaissance and baroque flutes have only six holes, while the modern flute (beginning rather early in the nineteenth century) has 7 and sometimes 8. Standard model cornetti have 6 finger holes, as I believe the low cornetti including lyzarden and serpent do. So, do we name the key of the instruments as the lowest sounding (6-finger) note, or the note that would be produced if the instrument did have 7 holes?

The answer is that we are marvelously inconsistent! The baroque flute is often referred to as a flute in D, but when an extension and a key were added, the same flute, playing at the same pitch, then became a flute in C. The standard cornetto is almost always referred to as being in A (the 6-finger note) and the cornettino as being in D (the 6-finger note).

Since I play and teach a number of historic woodwinds, I use a terminology that as a practical matter makes it easier for students to understand the relationships among instruments. So the baroque flute is "in C without a low C." This makes perfect sense to a modern flutist because on both instruments the 6-finger note is D and the 3-finger note is G.

Similarly the cornetto is "in G (as were most renaissance alto woodwinds) without the low G," and the cornettino "in C without the low C." (Of course if you start talking about the Irish 6-hole whistle the situation becomes completely confused, because the "natural scale" of a 6-hole whistle in D is a D scale, and one can argue that the same applies (and it does) to the early flutes!)

So, to return to the land of serpents, does calling a serpent "in D" or "in C" refer to the 6-finger note or to the theoretical 7-finger note?

Transposing Instruments

by Brian Blood

A transposing instrument is a musical instrument where what is written is not what is heard, i.e. the written pitch differs from the pitch that the instrument sounds. The written pitch is actually a transposition of the sounding pitch. It should be understood that transposing instruments are not themselves peculiar, only that the convention employed when writing parts for such instruments differs from that used for non-transposing instruments where, subject to a transposition of one or more octaves, the written note is the same as the note heard.

Where the instrument has a range that does not lie within the normal clefs, the music may be written either an octave lower than it sounds (e.g. piccolo, descant recorder) or an octave higher (e.g. double bass, contrabassoon, bass guitar, guitar, tenor male voice). Although these are strictly 'transposing instruments', most authorities do not describe them as such.

As we saw earlier, much of western music uses a notation that describes the sound that is required in terms of its pitch, duration and volume, rather than what you have to do with the instrument to produce the note; i.e. this fingering on a woodwind or brass instrument, that position for a finger on a string, and so on. Using the standard western music convention the same piece of music may be played on a whole range of different instruments, e.g. violin, flute, oboe, piano, guitar, voice, glockenspiel. A musician may 'read' a piece of music without necessarily knowing anything about how a particular instrument is played.

Unfortunately, under certain circumstances and despite its simplicity, this standard convention is not always the most convenient, and alternatives have been developed that address certain problems.

It would be convenient if a player, having associated one set of fingerings with a particular instrument, could play all the sizes of the same family of instruments, where the sequence of fingering remains the same as one moves up or down a chromatic scale, even when the family members are in keys that differ from that of the instrument with which the player has been first acquainted. In this case, the player would far rather be told prompted for the fingering he or she should employ to sound any required note, than having to know what note will actually sound.

For example, the standard transverse flute is pitched in C and is non-transposing, i.e. when the flute player reads a C, the note you hear is a C.

The alto flute, which is effectively the same instrument, only longer, and therefore at a lower pitch, produces a G a fourth lower when the player uses the same fingering as he or she uses on a standard flute.

Alto flute music is transposed up a fourth - a G in an untransposed part is written in the transposed part as a C, a fourth higher. The alto flute player reading C in the transposed part fingers the alto flute exactly as if he or she were playing the written note on a normal transverse flute in C, and the required note, a G, sounds.

If the composer want an alto flute to sound a C, he or she will write an F, a fourth higher, in the transposed alto flute part.

The result is that flute players can swap between instruments without having to learn two different 'note read - note heard' conventions.

A similar approach is used for many other families of musical instruments.

For example, clarinets come in various sizes and hence pitches (A, Bb, C, Eb), but the music is transposed appropriately for each size of instrument so that the player can happily move from one to the other. The only complication is that the most common sizes of clarinet are Bb and A; this means that people tend to say 'the clarinet is a transposing instrument' which, while broadly true, is not the case for the C clarinet. On the C clarinet, the note read is the note that sounds.

Some families of transposing instruments are:

• most members of the clarinet family (clarinet in A and Bb; high clarinet in D and Eb; bass clarinet in Bb; contrabass clarinet in Eb and Bb)
• some members of the oboe family (oboe d'amore, cor anglais in F)
• the saxophone family (there are saxophones in C though, thus non-transposing)
• the trombone family is treated as transposing instruments in band scores
• most brass instruments, notably the trumpet in B flat, the bass trumpet in E flat, the bass trombone in E flat and the French horn in F.