Prelude in C Major Question

The key of C major states that the piece uses only the notes from the C major scale, ie A to G, all natural.

But sometimes composers like to include a few extra notes, ones that are not from the scale, which in this case are the sharp or flats - and these are known as "Accidentals."

You can write any piece in any key in C major and then just write in all the sharps and flats sign, but this just clutters ip the page. So, the key signature just after the time signatures usually tells you which are sharps and which are flats. In C majar, there is nothing after the time signature, ie everything is natural unless otherwise stated.

Cool?

Mart.

The key of C major states that the piece uses only the notes from the C major scale, ie A to G, all natural.

But sometimes composers like to include a few extra notes, ones that are not from the scale, which in this case are the sharp or flats - and these are known as "Accidentals."

You can write any piece in any key in C major and then just write in all the sharps and flats sign, but this just clutters ip the page. So, the key signature just after the time signatures usually tells you which are sharps and which are flats. In C majar, there is nothing after the time signature, ie everything is natural unless otherwise stated.

Cool?

Mart.

hmm/ but isn't it a musicla rule that a song compose in C major should only have all natural notes,else it would sound out of harmony?

Not at all - you want a piece of music to have variety. Sticking to just the notes of the key can be limiting, so most composers include some 'outside' notes.

To add just a little info about accidentals.
If a note is marked by a sharp, flat or natural, all of the same note in the same measure following the marked note also follow the same rule.
Say for example there are 4 F notes in a measure and the 2nd one is marked sharp. You are in the key of C so the 1st F would be natural the last 3 would be sharp even though only the second one is marked. Any F notes in the next measure would revert back to natural (unless marked differently)

There's an exception to that, missleman - and some variations on the theme, too.

The exception is tied notes:any tied note with an accidental wll be affected for the duration of the tie... let's say you've got three consecutive notes on the top line, on beats 4, 1, and 2. The notes on beats 4 and 1 are connected by a tie, and the note on beat 4 has a sharp.

The publisher wants the performer to play F# (held for two beats) followed by F natural on beat two. That's called Traditional notation; it comes directly from classical composition.

Then you've got harp music... harps have to use a set of pedals to adjust notes, so reading accidentals can be a pain. Harpists would prefer to set the pedals according to the key signature, and then deal with any exceptions one by one. So a composer named Carlos Salzedo (1885-1961), who headed the harp department at the Curtis Institute, decided there had to be a better way - he figured every note should be a natural, unless it had an accidental. The Salzedo method uses sharps and flats, but no naturals - any accidental applies only to its note; a repeated F# requires repeated sharps, no matter where it falls.

Then there's the atonal music, starting with the Second Viennese School, the group of composers associated with Arnold Schoenberg... their music has loads of sharps and flats. They figured every note needed an accidental for clarity, so a sharp or flat applies to its note... but to save on ink, a note that's immediately repeated only needs an accidental the first time round - F#-F is two F# notes, F#-E-F is one F# followed by E natural and F natural in Second Vienna notation, sometimes seen as "Vienna II" notation.

A closely related variation on Vienna II is called Modernist notation. You might see a note on the front of sheet music indicating Vienna II or Salzedo - if so, you need to interpret the accidentals according to their method.

Still more notation systems have been created to handle modern music - the 'Equitone' system, which uses black or white notes to indicate chromatic pitches, and does away with accidentals altogether.

It's gonna get to be even more fun, with contemporary composers starting to explore microtonal stuff!