Instrument transposition
Play a "C" on a trumpet and a "C" on a piano at the same time and they don't match. That's transposition — and it confuses almost every beginner. Here's the simple version.
Concert pitch vs written pitch
Concert pitch is the actual sound — the pitch a piano, tuner, or guitar would call by that name. Written pitch is the note printed on a player's music. For some instruments these are the same; for others they're deliberately different.
Instruments where written and sounding pitch match — like flute, oboe, trombone, tuba, and piano — are called concert-pitch (or "C") instruments. Instruments where they differ are transposing instruments.
The common transposing instruments
- B♭ instruments (trumpet, clarinet, tenor sax, soprano sax): when they read and play a C, the note that actually sounds is B♭ — a whole step (major 2nd) lower.
- E♭ instruments (alto sax, baritone sax): their written C sounds as E♭.
- F instruments (French horn): their written C sounds as F, a perfect 5th lower.
Why on earth does this exist?
It's actually a kindness to the player. Each instrument family is built so that the same written note uses the same fingering, even on different-sized horns. A sax player can switch between soprano, alto, and tenor and the fingerings feel identical — the instrument's "key" takes care of the pitch difference. Transposition keeps reading and fingering consistent across a whole family.
What this means for practice
When a band director says "play a concert B♭," a trumpet or clarinet player plays their written C, an alto sax plays a written G, and a flute or trombone plays a written B♭. It sounds complicated, but you mostly just learn your own instrument's part — the transposition is baked into the music you're handed.
Brass Blaster
Pick your instrument and the game handles transposition for you — it listens at concert pitch but shows the notes in your written key, so you just play what you read. Brass & saxes. Mic required.
Want to check your tuning while you're at it? The free chromatic tuner can also show pitches in your instrument's written key.
Keep going: What is ear training? · Read the treble clef · all guides