Select an instrument and concert pitch to see the written pitch instantly.
Written Pitch for Bb Trumpet:
D
Transpose up a Major 2nd from concert C
1 Concert Pitch vs. Written Pitch
When a trumpet player reads and plays a C, the audience hears a Bb. This difference between what's written and what sounds is the essence of transposition.
Key Terminology
Concert Pitch: The actual sounding frequency. What the audience hears. What a piano would play.
Written Pitch: What appears on the page for a transposing instrument. What the player reads.
Non-transposing instruments (piano, flute, violin, etc.) have the same concert and written pitch. Transposing instruments have a built-in offset.
2 What "In Bb" or "In F" Means
When we say an instrument is "in Bb" or "in F," we mean:
The Naming Convention
The instrument's key tells you what pitch sounds when the player reads C.
Bb Trumpet: Player reads C → audience hears Bb
F Horn: Player reads C → audience hears F
Eb Alto Sax: Player reads C → audience hears Eb
3 The Transposition Intervals
Each instrument family transposes by a specific interval. Here's the complete reference:
Instrument
Key
Sounds...
To Write, Transpose UP
Bb Trumpet, Bb Clarinet, Soprano Sax
Bb
Major 2nd lower
Major 2nd (whole step)
F Horn, English Horn
F
Perfect 5th lower
Perfect 5th
Eb Alto Sax, Eb Clarinet
Eb
Major 6th lower
Major 6th
Bb Tenor Sax, Bass Clarinet
Bb
Major 9th lower (octave + M2)
Major 9th
Eb Baritone Sax
Eb
Octave + Major 6th lower
Octave + Major 6th
A Clarinet
A
Minor 3rd lower
Minor 3rd
Piccolo
C
Octave higher
Write octave lower
Glockenspiel
C
2 octaves higher
Write 2 octaves lower
4 Practical Tips
The Up/Down Rule
Writing for a transposing instrument? Transpose UP from concert pitch.
Reading a transposing part at concert pitch? Transpose DOWN.
Don't Forget Key Signatures
When transposing, the key signature changes too. If your concert key is C major and you're writing for Bb trumpet, the trumpet part should be in D major (two sharps).
Common Transposition Scenarios
Score reading: Look at horn in F part, mentally transpose down a 5th
Arranging: Write melody in concert key, transpose each part
Sight transposition: Trumpet players reading horn parts, etc.
Practice Makes Perfect
Our flashcard tool drills transposition until it becomes automatic.
Transposing instruments exist for historical and practical reasons. Within instrument families (like clarinets or saxophones), players can switch between different-sized instruments while using the same fingerings. This makes doubling easier. Additionally, many brass instruments evolved with specific overtone series, making certain keys more natural to write in.
How do I transpose from concert pitch to Bb trumpet?
To write for Bb trumpet, transpose UP a major 2nd (whole step) from concert pitch. If the concert pitch is C, write D for trumpet. If concert pitch is Bb, write C. The trumpet player reads C but the audience hears Bb.
How do I transpose for French horn in F?
To write for F horn, transpose UP a perfect 5th from concert pitch. If concert pitch is C, write G for horn. If concert pitch is F, write C. The horn player reads C but the audience hears F (a fifth lower).
What is the difference between concert pitch and written pitch?
Concert pitch is the actual sounding frequency—what you hear. Written pitch is what appears on the page. For non-transposing instruments (piano, flute, violin), these are the same. For transposing instruments (trumpet, horn, sax), they differ by a specific interval.
Do I transpose up or down when writing for transposing instruments?
When WRITING parts for transposing instruments, transpose UP from concert pitch. When READING transposing parts to find concert pitch, transpose DOWN. An easy way to remember: the written note is always "higher" on the page than the sounding note for common transposing instruments (Bb, F, Eb).
Further Study
Transposition is essential for arrangers, conductors, and anyone working with wind and brass instruments. These resources can help you go deeper:
Score study — Analyze orchestral scores to see transposition in context
Arranging practice — Take piano pieces and arrange for wind ensemble
Sight transposition — Practice reading parts in different keys