Clairnote DN has accidental signs that are similar to traditional accidental signs but they work a little bit differently. Much like traditional accidental signs they indicate:
- That a note is an accidental (i.e. not in the current key).
- The note's name, whether it is a sharp, flat, natural, double sharp, double flat, etc.
The difference is that unlike traditional accidental signs they do not indicate that the following note(s) should be played a semitone higher or lower (an essential instruction the musician must follow to play the right notes). Instead they effectively indicate that the following note has already been sharpened or flattened. They communicate the names of accidental notes but do not (typically) affect their pitch.  As such they play a very minimal role when it comes to reading and playing notes. For example, a piano or guitar player could ignore the accidental signs and still play the correct notes.
Here is an illustration of accidental signs in both systems:
Since Clairnote DN 's sharp and flat signs have a different meaning than traditional sharp and flat signs, new symbols are used — simple "matchstick-style" symbols pointing up for sharp or down for flat. These symbols are more visually subtle and take up less horizontal space than traditional accidental symbols.
Above is an illustration of two pairs of enharmonically equivalent notes — notes like the black keys on a piano that have different names but have the same pitch (in 12-tone equal temperament  ). In Clairnote DN it is much clearer that they have the same pitch. The alternative accidental signs simply indicate their different names and do not affect their pitch. (Differentiating between enharmonic equivalents using Clairnote DN 's accidental signs and Key Signatures makes it possible to use the standard Names of Notes and Intervals .  )
Clairnote DN 's accidental signs remain in effect until the end of the measure in which they appear, just like traditional accidental signs. Fewer accidental signs are needed because there are twelve staff positions per octave instead of seven. The following measure illustrates this point with its repeating melodic pattern of G, G-sharp, and A, where only the first G-sharp gets an accidental sign. Notice how Clairnote DN uses less horizontal space because it requires fewer accidental signs.
Below is a similar illustration showing alternating E-minor and E-major chords (triads in second inversion ).
Traditional notation often requires accidental signs that cancel previous ones in a given measure, but this is very rare in Clairnote SN. For it to happen there would have to be two different enharmonically equivalent notes in the same measure. For example, F-sharp and G-flat, or E and F-flat.
Clairnote DN has natural signs that indicate natural notes that are outside of the current key, just as in traditional notation. For example, an F natural note in the key of G major (where F is sharp) would have a natural sign, as shown below.  (See also Clairnote DN 's Key Signatures .)
Double sharps and double flats are indicated by doubled sharp and flat symbols.
To give a taste of Clairnote DN 's accidental signs in a more musical context, here is an illustration of an ascending and descending chromatic scale.
- This assumes the standard tuning system of 12-tone equal temperament. In other less commonly used tuning systems the pitch or intonation of "enharmonically equivalent" notes may differ slightly. In that case Clairnote DN's accidental signs and key signatures indicate these subtle shifts in pitch/intonation, as well as the different names of the notes. See the Enharmonic Equivalents tutorial on the Music Notation Project's site. Return
- Even if someone has no need to distinguish enharmonic equivalents and uses an alternative note naming system that does not differentiate between them, Clairnote DN's accidental signs are still useful since they indicate which notes are outside of the current key. This reassures musicians that they are playing the correct note, even if it may sound out of place. However, musicians can always just ignore them or even omit them, for example if they are creating sheet music with LilyPond . Omitting them may be especially appropriate for use with atonal or non-diatonic music. Return
- A different approach would be to use the same "matchstick" accidental symbols for natural notes. For example, indicating that a note was raised from B-flat (in the key signature) to a B-natural (as an accidental outside the key) by using an upwards-pointing matchstick accidental sign rather than a natural sign. This would more directly indicate that such accidental notes have been lowered or raised. However, it makes it harder to determine the names of accidental notes since there would no longer be a one-to-one correspondence between the name of a note and its accidental sign. Since Clairnote DN 's accidental signs are largely about communicating the names of notes, it uses natural signs to indicate natural notes. Thus the note's name (sharp, flat, natural) is always directly indicated by the accidental sign. Return