Transposition (music)

In music, transposition is understood to mean changing the pitch of notes by a certain interval or moving an entire piece of music into a different key, true to the interval .

The simplest type of transposition is octaving , in which the notes have the same name but are shifted one octave up or down. When transposing with other intervals, the key and thus the general accidentals must be changed in most cases . For example , if you transpose from D major to F major , you swap the two marked sharps (for “f sharp” and “c sharp”) for a b (instead of “b”) and then set all notes up by a minor third or major sixth down.

Historical instruments

With historical brass instruments ( e.g. natural trumpet or natural horn ), due to the lack of chromatic playability, it was not possible to play in keys that deviated far from the basic tuning (see also natural tone series ). Therefore, the musicians use interchangeable vocal arcs of different lengths (e.g. A-bend, C-bend, Eb-bend, F-bend on the trumpet) in order to change the basic tuning. In order to save the musicians from transposing and to make it easier to read, the (natural) tones were always notated in C major or without a general accidentals and indicated which slur or which tuning should be used. The tuning (= the bow) of the instruments was chosen based on the key of the piece, with combinations of different tunings being used to increase the tone supply. This happened especially with pieces in minor, in order to be able to realize their minor third (see Mozart Symphony No. 40 in G minor ).

From the beginning of the 20th century, fixed tunings for wind instruments became established (trumpet in Bb or C, horn in F). This is why older compositions have to be transposed for other moods. In the modern symphony orchestra this applies to the trumpets and even more so to the horn players. It is unusual for horn players to use transposed parts. If you are practiced to play in all common transpositions, the notation is very clear, as it does not have a general accidentals. Furthermore, it can be seen at first glance which notes on the natural horn had to be played openly and which were stuffed, which can be balanced dynamically and technically.

Change the pitch of your voice

Often, songs or other pieces are too high for one voice ( Franz Schubert, for example, wrote his songs for high voice). This is where transposing to a more suitable position can be of great help. This tradition is maintained by musicians to this day: Most of the song cycles of the great composers have their own editions for the different voices , which have been transposed into the corresponding keys. Arrangements for (big) band with vocals are also traditionally adapted to the optimal vocal range of the singer. The same goes for music lessons in school.

The possibility of transposition, however, tempts beginners in particular to avoid technical difficulties that could be overcome with a little practice and instruction and which could open the way for a gradual expansion of the vocal range.

In instrumental music, a piece that “lies” comfortably on the flute, for example, can be uncomfortable and too high for an oboist and is better played by him in a lower register. Johann Sebastian Bach , who often reworked his own melodies or entire pieces for other instruments, used this practice again and again.

Technical relief

When pieces of music are in difficult keys, it is often difficult for beginners to cope with the abundance of accidentals . The famous English horn solo from Antonín Dvořák's Symphony From the New World , which is originally in D flat major, could be transposed to C major in a piano album for children, so that it can only be played with white keys:

(a) Dvořák's New World in the original, (b) in a lighter version

But it can also be useful for professional instrumentalists to transpose a piece of music: Works for wind instruments are often in B-flat keys and those for strings in sharp keys , because this suits the sound and technique of the instruments. If a cellist plays a bassoon piece in A flat major , it can sound more brilliant and natural if he transposes it into a key that is more comfortable on the cello, such as A major .

Practice of transposition

Example 1: the start tone (red)
Example 2

In principle, a trained musician should be able to transpose a musical text by certain common intervals. You can do this e.g. B. practice by transposing a given melody upwards by chromatic intervals ("semitones"). The main practice is to transfer the read intervals to the intervals to be played based on the new starting tone (example 1). The level of difficulty increases enormously if, instead of a unison melody, e.g. B. has to transpose a complex piano setting or a melody with many accidentals and jumps.

Example 3
Example 4

When transposing a semitone, you mentally put the accidentals of the new key at the beginning, where z. B. a marker becomes a cross, a cross ( # ) disappears or a Be ( b ) becomes a marker (example 2).

Other intervals can be transposed by mentally changing the key and / or the sign with a corresponding octave (Examples 3 and 4).

Absolute listeners represent a special case . For example, if a relatively hearing singer only notices that the melody is higher or lower, the absolute hearing singer must mentally understand the transposition correctly. Under certain circumstances it can happen with difficult interval jumps that the original sound is sung instead of the transposed sound. The same phenomenon can work with instrumentalists, since the absolute listener usually associates fixed pitch locations on his instrument with the notes he sees.

Transposing instruments

Transposing instruments usually have individual parts in the notation that are already transposed, so the musician does not have to worry about it, but plays what is written in the notes, and it sounds the right pitch. The following excerpt from Beethoven's Fifth Symphony shows the voice of the Bb clarinets , which sounds a whole tone lower than you write it down. (a) is the (upwardly transposed) printed voice, (b) is the desired and achieved sound one whole tone deeper.

Transposition on the Bb clarinet

Sometimes, however, a musician has to play on his "transposing" instrument from a so-called C part that is not written transposed , for example a clarinetist who takes on the part of the flute or violin. In this case, the transposition must be done in real time in the musician's mind.

In orchestral literature you can sometimes find C clarinet parts, for example in Beethoven's or Schubert's symphonies, or Rossini'sBarber of Seville ” , whose sometimes extremely fast passages are much easier to master on the C clarinets, which are hardly used today would be. In some works by Richard Strauss and Richard Wagner there are also parts for a bass clarinet in A, which in the absence of such instruments must be played a semitone lower than notated with a bass clarinet in Bb.

Particularly complex can at bugler be that in nature Horns have to cope with a variety of transpositions. The figure below shows another excerpt from the Beethoven symphony: The notes say (a) , should sound (b) , what the F horn (c) has to be fingered for:

The double transposition from old horn parts

Electronic transposition (sampling)

Transposition as a percentage

With a sampler , the tones sampled from the original instruments can be transposed.

• If the playback speed is changed at the same time, the pitch also changes (similar to a record ). However, this also changes the timing of the sound, which worsens the result. A clear example is the so-called "Mickey Mouse voice" in electronically highly transposed recordings.
• The computationally more complex processing of the sample “slice by slice” is different, in which extremely short temporal segments of the tone oscillation are played back faster and then duplicated in such a way that the length of the sound does not change. The problem with this method is the shifting of the formants , because a higher / lower played or sung tone usually has a different sound characteristic than an electronically transposed one.
Transpositionstabelle (in Prozent):
-8    158,74
-7    149,83
-6    141,42
-5    133,48
-4    126,00
-3    118,92
-2    112,25
-1    105,95
keine 100,00
1     94,39
2     89,09
3     84,09
4     79,37
5     74,92
6     70,71
7     66,74
8     63,00


It follows the exponential function

${\ displaystyle f (x) = 100 \ cdot 0 {,} 9439 ^ {x} \,}$.

Double or half the frequency is achieved with a transposition of 12 semitones. From this, the frequency ratio of two adjacent semitone steps in the equal tuning is derived: The twelfth root of 2 (the octave) is 1.059463094 or its reciprocal: 0.943874313.