Music scores, whether orchestral, concert band, big band, or a pop chart etc. typically contain a variety of differently pitched instruments. Because factors like instrument length, size and acoustical properties affect each instrument’s range / tessitura, certain instruments need to be written transposed, in a different octave, or both to produce pitches in common with other instruments.
This system of written pitch notation allows the music to remain largely within the staff for each part as well as the transposing score. Instruments written in a different octave than where they sound are referred to as octave-displaced instruments.
Additionally, it is common practice in Concert Scores to show octave-displaced instruments at written (rather than concert) pitch. This allows these instruments to be notated largely within the staff. (For Finale users, more on this later.)
TRANSPOSING INSTRUMENT TYPES
Regardless of whether a pitched instrument produces its sound by vibrating metal, membranes, strings or air, it falls into one of the following four transposition / octave displacement types:
1) Instruments at Concert Pitch
Examples: Flute, Oboe, Bassoon, C Trumpet, Harp, Piano, Marimba and Vibraphone.
These instruments sound where written, e.g. the part and score are identical visually as well as sounding regardless of whether the score is displayed Transposing or in Concert Pitch.
2) Transposing Instruments Without Octave Displacement
Examples: Bb Clarinet & Bb Trumpet. These sound down a Major 2nd from where written – e.g. to hear a sounding C, you must write a D a whole step above the desired sounding pitch.
French Horn & English Horn. These sound down a Perfect 5th from where written – e.g. to hear a sounding C, you must write a G a perfect 5th above the desired sounding pitch.
3) Transposing Instruments With Octave Displacement
Examples: Bb Bass Clarinet and Bb Tenor Sax. These sound down a Major 2nd + 1 Octave from where written (down a Major 9th from where written). e.g. to hear a sounding C, you must write a D a whole step + 1 Octave above the desired sounding pitch (e.g. written up a Major 9th).
4) Octave-Displaced Instruments
Examples: Piccolo, Celesta and Xylophone (these sound up a perfect octave) e.g. to hear a sounding C, you must write a C one octave *below* the desired sounding pitch.
Guitar, Electric Bass, Bass Flute, Bass Oboe, Contrabassoon (these sound down a perfect octave) e.g. to hear a sounding C, you must write a C one octave *above* the desired sounding pitch.
Glockenspiel (sounds up 2 Octaves, or 15ma) e.g. to hear a sounding C, you must write a C two octaves *below* the desired sounding pitch.
In both Finale and Sibelius, support for these transposition / octave displacement conventions are already built in for Transposed Scores. Your score will display all notation correctly in both the score and the parts, as well as play back your at the correct pitches.
CONVENTIONS FOR CONCERT PITCH
It turns out that Octave Displaced instruments have an additional unique convention, at least for Concert Pitch scores.
If you’ve spent any time reviewing modern scores written in Concert Pitch, you may have noticed that octave-displaced instruments appear in the score at *written* pitch (e.g. the pitch that the player sees in their respective parts) rather than concert pitch.
Fact: Commercial film scores are written almost entirely in Concert Pitch, with all octave-displaced instruments at written pitch, and without a Key Signature (Keyless).
The reason for this convention is that allows the music for these instruments to appear largely within the staff rather than being displayed with a number of ledger lines for these frequently extreme ranges.
In your notation program, support for this convention may or may not be built in (Sibelius supports it, Finale does not as of Finale 2014), and must also extend to playback, so that these octave-displaced instruments play back correctly.
Thanks for reading!
If you are a Finale user working in Concert pitch scores, be sure to check out “Octave Transposed Staves in Concert Scores with Transposed Parts in Finale“.