Three strings, one letter changes everything
A mountain dulcimer has three strings (or four, with the melody string doubled into a unison pair). The bass and middle strings almost never move: D3 and A3. What names the tuning is the third letter — the melody string. Tune it to D and you have DAD; tune it to A and you have DAA. Same instrument, same first two strings, completely different playing experience.
- D3Bass string · thickest146.83 Hz
- A3Middle string220.00 Hz
- D4Melody string · doubled on 4-string dulcimers293.66 Hz
Highlighted rows are the melody string — the only one that changes between these tunings. Tap a tone to hear the target, or play each string into the tuner above and center the needle.
DAD or DAA — which do you want?
| Tuning | Mode | Major scale starts at | Known for |
|---|---|---|---|
| D–A–D | Mixolydian | 3rd fret | Today’s standard — chords, cross-string playing, jam sessions |
| D–A–A | Ionian | 3rd fret | The traditional tuning — drone-and-melody, old-time repertoire |
| D–A–C | Aeolian | 1st fret | Minor-key tunes |
| D–A–G | Dorian | 4th fret | Modal fiddle tunes |
If you are learning from a modern book, a video course or playing with other people, tune DAD — it has been the default for decades because the melody string and bass string are an octave apart, which makes chord shapes fall under the hand. If you are working from older traditional material, or you want the classic sound of a melody played against two ringing drones, tune DAA.
Tuning order
- Bass string first: D3. The thickest string, closest to you when the dulcimer is on your lap. Everything else gets checked against it, so settle this one before moving on.
- Middle string: A3. A perfect fifth above the bass. Once it is centered, play the two together — a fifth is a wide, hollow, stable sound, and beats between them are easy to hear once you know to listen.
- Melody string: D4 for DAD, A3 for DAA.Watch the octave number on the dial here. D3 and D4 are both “D”, so the octave display is what tells you the melody string is an octave above the bass and not accidentally in unison with it.
- On a 4-string dulcimer, tune the melody pair last and together. Both strings go to the same note. A pair a few cents apart warbles — bring the second string up until the warble slows and stops.
Capos, and why D matters
Dulcimer players change key with a capo far more often than they retune. Capo at the 1st fret and DAD becomes E; capo at the 3rd and you are in G — the standard session key. That is the practical reason nearly everyone stays in D-based tunings: it keeps the capo positions predictable and the fret markers meaningful. Retune the melody string only when you actually want a different mode, not a different key.
Hammered dulcimer
A hammered dulcimer is a different instrument entirely — dozens of courses of two to five strings each, struck with small mallets, with no frets and no single “tuning” to name. The tuner above still works, and in fact a chromatic tuner is essential equipment for one: work bridge by bridge, tune every string of a course to the same pitch until the course rings clean, and expect the whole job to take a while. Because you are checking a hundred or more strings, the octave display matters — it is the fastest way to catch a course that has slipped a full octave rather than a few cents.
Frequently asked questions
Is this a real dulcimer tuner, or just a generic tuner app?
It is a chromatic tuner, which is what a dulcimer actually needs — it names any note it hears rather than only recognizing three fixed targets. That means the same page handles DAD, DAA, DAC, DAG, anything you invent, and a hammered dulcimer’s full range. The reference tones above give you the standard targets; the dial handles everything else.
What is the difference between DAD and DAA tuning?
Only the melody string. In DAD it is tuned to D4, an octave above the bass string, giving the Mixolydian mode from the open string and putting the major scale at the 3rd fret. In DAA it is tuned to A3, in unison with the middle string, giving Ionian with the major scale also starting at the 3rd fret but played against two drones instead of one. DAD is the modern standard and better for chords; DAA is traditional and better for drone-and-melody playing. Full walkthrough in our mountain dulcimer tuning guide.
Do I need to install an app?
No. Everything runs on this page through your browser’s microphone — no install, no account, no ads. It works the same on a phone propped next to you, a tablet or a computer, and the reference tones work with no microphone at all if you would rather tune by ear.
My dulcimer will not stay in tune. What is wrong?
Usually nothing. Friction pegs hold by pressure alone — push firmly inward while turning, the way a violin peg works. Beyond that, dulcimers are light instruments that respond quickly to temperature and humidity, and fresh strings stretch for days. If a single string keeps slipping while the others hold, that peg needs attention; if everything drifts together, the room changed, not the instrument.