Why middle C?

Why middle C?

By Terry Relph-Knight, copyright retained 03/06/18

Most people will have heard of middle C, but apart from knowing it is a musical note somewhere around the middle of the piano keyboard, won’t know it’s significance. Why C? Why middle? 

Guido the Monk

The existence of western musical notation and consequently middle C, is due to the Catholic Church seeking uniformity in church worship. The church leaders were concerned about heresy, they wanted to be sure that wherever Christianity was practised, everyone followed the same dogma; they believed the same things and all worshipped in the same way. In the 10th century, plainsong or plain chant – unaccompanied singing performed by monks and boys – was a part of religious services. The problem was there was no accurate system of writing music. All they had was a series of marks or neumes above the written words of the chant. This did little more than indicate that the next note went up or down in pitch and provided some idea of the articulation. Chants had to be memorized and could only be taught directly from one person to another. There was always the possibility for mistakes to creep in, or for music to be lost altogether.

Why middle C ?

A musical theorist, a monk known as Guido of Arrezo https://en.wikipedia.org/wiki/Guido_of_Arezzo or sometime just Guido Monaco (the monk), solved the church’s problem by inventing the basis of western musical notation.

He took the neumatic notation and extended it into a five line staff or stave. Five lines are a small, easily drawn and read number. Notes are written either between, or on the lines, and by placing the bottom note in a sequence just above the bottom line, then counting all the spaces and lines and ending immediately above the fourth line, you get seven notes. The eighth note in the sequence is of course the octave, so a five line staff can comfortably cover one octave. To cover wider ranges of pitch, further sets of five staff lines can be used and short extension ledger lines can be drawn above or below the five line staff. Each staff is separated by at least a single ledger line which isn’t drawn as a continuous line, leaving space between staves for the purpose of legibility.

Guido based his system on the pitch range of the male human voice. The overall pitch of a five line staff is indicated by a clef sign (clef from the French, meaning key) at the beginning and Guido started with two pitch ranges of bass and treble. He used the letters of the Roman alphabet to name the notes and he chose to start with A in the gap between the bottom line of the bass clef and the next line up. He then carried on naming the seven notes of the major scale in alphabetic order, as B, C, D and so on, ending on the seventh as G just below the top line. The next note is the octave A, the same as the starting note only twice the frequency, and the seven letter sequence repeats. 

So, despite the modern practice of referring to a C to C octave, the note sequence originally started logically with the letter A, not C. For tuning purposes the reference note is usually an A. The frequency of this reference note has varied over time. Only relatively recently in the early 1900’s has orchestral pitch settled (more or less) on an A of 440Hz which puts ‘middle’ C at 261.63Hz (Hertz or Hz is cycles per second in old money).

Guido was creating musical theory in the 10th century to suite the church music of the time. This was modal music based on six note hexachords. Now a thousand years later musical complexity and musical taste have changed and the C major scale, the only major scale with no sharps or flats, is central to Western music. The C to C major scale organisation of the white keys on the piano, an instrument not even thought about in Guido’s time, along with the five black keys, is an easily recognised pattern and the piano keyboard is often used as a reference. If we were to re-write musical theory and the method of musical notation today, we might choose to re-label the notes.

The Grand Stave


The Grand Stave

The Grand Stave

The Grand Stave covers a span of three octaves, with the treble clef above the bass clef, divided by the single ledger line occupied by Middle C

If you stack a treble stave above a bass stave you get two sets of five lines separated, for clarity, by a single ledger line (and a space above and below it). Although never used in written music this is known as a grand stave or staff. Following the Guido system, starting with A in the bass clef you will find the note letter that sits on that central ledger line is a C. This is where middle C comes from, for the grand stave it is the central note between the bass and the treble staves. 

The bass clef symbol is a stylised letter F with the two dots split by the stave line for the note labelled F and the treble clef symbol is a stylised letter G with the centre curl of the letter on the stave line for G.

The Grand Stave covers a range of three octaves. A good fit for the range of the average human voice, which is around three and a third octaves. The range of many instruments doesn’t extend much further, although their overall pitch may be higher or lower. 

In written music with treble and bass staves the two are written spaced apart and high notes in the bass or low notes in the treble are given their own short ledger lines, rather than migrating across from one stave to the other. Multiple ledger lines are often used, but beyond four or five ledger lines the notation becomes hard to read and at this point the notation may switch staves. The assumption is that the treble and bass parts will be performed on different instruments and music is more easily read if the parts are separated. Instruments such as the piano, that can span across the bass and treble, still have the parts written on separated staves because the left hand plays the bass and the right the treble.

Written guitar music

It is a curious fact that the modern guitars pitch range places it in the bass clef, but guitar music is usually written an octave higher in the treble stave. This can cause problems for session guitarists expected to play from a score written by a composer that doesn’t know the real pitch of the guitar. The F of the bass clef is normally pitched at 174.61Hz. The low E of the guitar is the second E below that, at 82.41Hz, located on the first ledger line below the bass stave.

There are other clef symbols than the treble and bass G and F clef’s. For example the alto clef, which is well suited for the pitch range of cello music and as it happens, guitar. And the tenor clef. In total there are ten clefs that have been used in musical notation. However these ‘specialist’ clef’s are rarely used, it’s just simpler to use the treble and bass clef’s and transpose parts to fit.

The reason for this pitching oddity is that early guitars, like many string instruments even today, had only four strings (or more accurately – four courses of two strings each). The name “guitar” derives from the Old Persian “chartar”, which literally means “four strings”. Many four string instruments, like the violin, are often played in ensemble and rather than having strings added to expand the range, are part of a family of instruments. For the viol family we have, roughly speaking, the violin, the viola, the cello and the double bass. Both the Cremonese old masters – Amati, Stradivari and Guarneri del Gesu – and modern makers have supplemented this range with other sizes of instrument. Traditionally the viol family is used classical orchestras and the frequency range is expanded by the use of different sizes of the basic instrument design. In comparison the guitar is not considered an orchestral instrument, rather it is an instrument that is often played on its own, or in small groups. Although we do have the bass guitar and the rarely seen, short scale Terz guitar. The four string tenor guitar doesn’t really count as part of the guitar ‘family’ because it is really a banjo with a guitar body.

Over the years, just as with the lute, which started life as a four string instrument, composers and players sought to extend the range of the guitar and it acquired a fifth bass string and then a sixth. This is one of the things which makes the guitar a special instrument, these extra strings make it possible to play a bass line, rhythmic chord patterns and melody lines all at the same time. Altered tunings extend these possibilities even further. It is quite natural to down tune the two bass strings and play a bass line on those, with the top four strings for chords and melody.

As to why western music uses seven notes for a major scale and eleven notes including sharps and flats (or 8 notes and 12 notes if you include the octave) is a question for a another time.