transposing instruments: what is written and what you hear
a transposing instrument reads notes that differ from the pitch it sounds, so its sheet music is written in a different key from the concert score. when a trumpet player reads a written C, the note that comes out is the B♭ a whole step below it.
concert pitch and written pitch
concert pitch is the actual sound: the note a piano, flute or violin would play to match it. written pitch is what appears on the player's part. for C instruments the two are the same. for a B♭ instrument, a written C sounds as concert B♭, so every note on the part sits a whole step above the sound. a conductor's score is often printed in concert pitch so the harmony is easy to read, while each player's part is printed in that instrument's own key.
why instruments transpose
the main reason is fingering. saxophones come in several sizes, and a player who learns one can pick up any other because a written note uses the same fingers on all of them. the sound shifts with the size of the instrument, but the reading does not. clarinets and brass work the same way, and the habit dates back to natural horns and trumpets, which changed key by swapping lengths of tubing called crooks.
the guides
each guide has the interval, a written-versus-concert example in note names, the usual range and tips for writing the part.
| instrument | pitched in | to write the part from concert pitch | guide |
|---|---|---|---|
| trumpet | B♭ | up a major 2nd | B♭ trumpet guide |
| clarinet | B♭ (also A and E♭) | up a major 2nd for B♭ | clarinet guide |
| alto saxophone | E♭ | up a major 6th | alto sax guide |
| tenor saxophone | B♭ | up a major 9th | tenor sax guide |
| French horn | F | up a perfect 5th | French horn guide |
a quick rule for each key
for B♭ instruments, write a whole step higher than concert pitch; tenor sax and bass clarinet go up a further octave. for E♭ instruments, write a major sixth higher, which lands on the same letter as going down a minor third. baritone sax adds an octave to the alto's interval. for instruments in F, write a perfect fifth higher. the key signature moves by the same interval: concert B♭ major becomes C major for trumpet, G major for alto sax and F major for horn.
checking your work
a band tunes to concert B♭, which makes a handy check. trumpets, clarinets and tenor saxes should be reading C, alto and baritone saxes G, and horns F. if a part disagrees, the interval went the wrong way. the transposer does the conversion for note names and chord symbols, and the circle of fifths shows every key signature you might land on.
common questions
what is a transposing instrument?
an instrument whose music is written at a different pitch from the one it sounds. a B♭ trumpet plays a written C and you hear the B♭ a whole step lower, so its part is written a whole step above concert pitch.
which instruments are transposing instruments?
in a band or orchestra: B♭ trumpet, cornet, clarinet, soprano and tenor sax; E♭ alto and baritone sax and E♭ clarinet; A clarinet; horn and English horn in F. flute, oboe, violin, piano and trombone read at concert pitch.
what does concert pitch mean?
the actual sound. a concert C is the C a piano plays. a score in concert pitch shows every instrument at the sounding note, which makes the harmony easy to read; the players' parts are then transposed for each instrument.
how do I transpose a part quickly?
use the interval for the instrument: up a whole step for B♭, up a major 6th for E♭ alto, up a perfect 5th for F horn. the transposer does it for note names and chord symbols, and notei's notation editor writes transposed parts for you.
sources
- Wikipedia: transposing instrument
- Wikipedia: concert pitch
- Open Music Theory: core principles of orchestration
this hub is part of the how to write sheet music series, and the band and choir guide puts the parts together. notei publishes these guides, and notei is our product.
writing for band or orchestra? notei is a free music notation editor in the browser. its Transpose tool moves a passage or a whole score to a new key.
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