Press valves 1 and 3, play low D, and look at a tuner. On most B♭ trumpets the needle sits well to the sharp side while your open notes read centred. Nothing is wrong with your horn. A three-valve trumpet has a handful of notes that lean sharp or flat by design, and each one has a standard fix.
01 Why valves pressed together play sharp
Each valve adds a loop of tubing cut for the open horn: valve 2 lowers it a half step, valve 1 a whole step, valve 3 a step and a half. Press two at once and the second loop is lowering a horn that is already longer, which needs a longer loop than the one it has. The tube comes up short, so the note comes out sharp.
With each valve cut exactly for its own step, 1-3 plays about 30 cents sharp and 1-2-3 about 54 cents sharp. A cent is a hundredth of a half step, so 54 cents is past halfway to the next note. 1-2 and 2-3 are short too, by roughly 11 and 16 cents: small enough to lip, big enough to show on a held note.
02 The one partial that sits flat
Every valve combination plays a ladder of notes, the harmonic series of that length of tube. Most rungs land within a couple of cents of a piano note. The 5th rung doesn’t: it sits about 14 cents under the piano’s major third. So the notes built on it lean flat, and they are all near the top of the staff: open E5 and E♭5 on valve 2 in the top space, D5 on valve 1 on the fourth line.
C♯5 lives on the same rung but uses 1-2, which leans sharp. The two errors mostly cancel, and on a lot of horns C♯5 comes out close.
03 Note by note: the usual lean and the fix
| Written note | Valves | Typical lean | Fix |
|---|---|---|---|
| F♯3lowest note, three ledger lines down | 1-2-3 | Very sharp · about +54¢ | 3rd slide out a long way; add the 1st slide if your horn has a saddle or trigger |
| G3low G, below the staff | 1-3 | Sharp · about +30¢ | 3rd slide out |
| C♯4low C♯, first ledger line | 1-2-3 | Very sharp · about +55¢ | 3rd slide out further than for D; 1st slide as well if you can |
| D4low D, under the staff | 1-3 | Sharp · about +32¢ | 3rd slide out |
| E♭4bottom line | 2-3 | A little sharp · about +17¢ | 3rd slide out a little |
| E4bottom line | 1-2 | A little sharp · about +13¢ | 1st slide out a little |
| A♭4second space | 2-3 | A little sharp · about +16¢ | 3rd slide out a little |
| A4second space | 1-2 | A little sharp · about +11¢ | 1st slide out a little |
| G4 and C5second line, third space | open | Close to centre | Set the main slide on these |
| C♯5third space | 1-2 | Usually close · about −3¢ | Check it: sharp valves on a flat partial mostly cancel |
| D5fourth line | 1 | Flat · about −14¢ | Faster air and firm corners; there is no slide to push in |
| E♭5top space | 2 | Flat · about −14¢ | Same as D5 |
| E5top space | open | Flat · about −14¢ | Same as D5, or compare 1-2 on your tuner |
The same pattern repeats an octave down: A♭3 on 2-3 and A3 on 1-2 lean a little sharp, like the same fingerings in the staff.
What the cents are
Textbook numbers from valve lengths and the harmonic series. They show the direction a typical horn leans and roughly how far.
What they are not
A measurement of your trumpet. Bore, leadpipe, mouthpiece and how you blow all move these, sometimes a lot. Every horn differs; the tuner has the last word.
04 Set the main slide before anything else
- Play for a few minutes first. A cold trumpet plays flat, and the pitch creeps up as your breath warms the tubing.
- Hold an open note at a comfortable medium volume: written G4 on the second line or C5 in the third space. A concert-pitch tuner calls them F and B♭. If your band tunes to concert B♭, that is your written C.
- Look at the tuner once the note has settled. Sharp: pull the main slide out a little. Flat: push it in.
- Check the other open note. If G and C disagree, split the difference instead of chasing one of them.
- Leave it there. From now on the 1st and 3rd slides deal with single notes.
Two traps. Don’t fix low D with the main slide: pull it out far enough to centre D4 and every open note goes flat with it. And if E5 is the only open note reading flat, leave the main slide alone. That is the 5th rung doing what it always does.
05 Move the slides while you play
3rd slide · the ring
Most trumpets have a ring on the 3rd-valve slide for your left ring finger. Push it out as the 1-3 or 1-2-3 note starts and bring it home on the next note. If you wait to hear the sharp note first, you are already late.
1st slide · saddle or trigger
Many horns add a thumb saddle or trigger on the 1st-valve slide. A small push lowers E4 and A4 on 1-2; on low C♯ it helps when the 3rd slide alone isn’t enough. No saddle? Lip those notes down a hair, or let a short one go.
06 Long tones with a tuner, without staring at it
Pick three notes from the table, say D4, E4 and E5. Hear each one in your head, play it for eight slow counts at a steady medium volume with your eyes on the music, then glance at the tuner. Pencil a + or a − beside the note. Tomorrow, set the slide before the note starts. Watching the needle the whole time teaches your eyes to fix the pitch after the fact; the glance teaches your ear to place it first.
The flat notes have no slide to push in. Lift them with faster air and firm mouth corners. Pinching the lips together or pressing the mouthpiece harder does raise the pitch, but the sound thins out and your lips tire long before the end of a rehearsal.
Related reading
Questions
Why is low D sharp on trumpet?
Low D uses valves 1 and 3 together. Each valve's tubing is cut for its own step, so together they come up short and the note plays sharp, about 30 cents on paper. Push the 3rd-valve slide out as the note starts.
Which trumpet notes are naturally flat?
The notes on the 5th partial: D5 on the fourth line (valve 1), and E♭5 (valve 2) and E5 (open) in the top space. They sit about 14 cents flat of a tuner's equal temperament. Lift them with faster air and firm corners rather than pinching.
Should I tune my trumpet before or after warming up?
After. A cold trumpet plays flat and the pitch rises as your breath warms the tubing, so set the main slide once you have played for a few minutes.
Do all trumpets have the same out-of-tune notes?
The direction is the same on nearly every three-valve trumpet, because it comes from valve and harmonic arithmetic. How far each note leans differs from horn to horn, so check yours with a tuner.