What a tuning drone is for
A tuner tells you whether one note is exactly right. A drone teaches your ears to keep it right while you play, which is a different skill and the one that actually decides whether you sound in tune in a section, a quartet or a band. When your note sits exactly on the drone, or on a pure interval above it, the two sounds fuse. When it is a few cents off, they beat: a slow pulsing in the loudness that speeds up as the error grows and stops dead when it is gone. Practising against a drone is practising hearing that pulsing and removing it, until the adjustment happens before you have consciously noticed the problem. The full guide to drone practice covers the mechanism and a routine that uses a drone and a tuner together; this page is the drone itself.
How to use this drone
Pick the note. Tap a key on the keyboard, then set the octave. For a scale or a study, choose its key note. For open-string work, choose the string. For long tones, A is the usual pick, because it is what an ensemble tunes to.
Set the reference pitch. A4 = 440 Hz is the standard; set 442 if your orchestra tunes there, 415 for baroque pitch. The drone re-pitches automatically, and every note on the keyboard moves with it, exactly as the reference pitch setting in the app moves both the tuner's target and the drone together.
Start it, then play. Hold your note against the drone and listen for the beating. Slide until it stops, then try to land on the note cleanly the first time. Play slow scales over the key note and listen to every degree settle; play fifths and octaves above it and listen for the interval locking. Stop when your ears tire, which is sooner than you think; ten focused minutes beat a distracted hour.
Check with a tuner afterwards. Not during: a microphone in the same room hears the drone and locks onto it. Stop the drone, then check your note with a tuner you trust. If the ears and the needle agree, the practice is working.
Which note, for which instrument
| Instrument | Open strings or usual drone notes |
|---|---|
| Violin | G3, D4, A4, E5 |
| Viola | C3, G3, D4, A4 |
| Cello | C2, G2, D3, A3 |
| Guitar | E2, A2, D3, G3, B3, E4 |
| Bass guitar | E2, A2, D3, G3 (the drone sounds one octave above the low strings, which still locks cleanly) |
| Winds, brass, voice | The key note of the piece, or A3 / A4 / Bb3 for long tones |
| Indian classical, modal practice | Your Sa (the tonic), with the Octave blend for a tanpura-like fullness; see the online shruti box for choosing Sa and practising swaras against it |
Pure or warm, root or octave
The Pure voice is a single sine wave at exactly the note. It is the cleanest reference there is, but it gives you only one place to hear beating, right at the fundamental, so small errors are easy to miss. The Warm voice adds a stack of harmonics above the note and a gentle shimmer around it, the way a reed organ or a harmonium does. Your own instrument carries harmonics too, so now every pair of harmonics that lands near each other can beat, and a small error shows up in several places at once. Use Warm when you are actually practising intonation and Pure when you want an uncluttered reference.
The Octave blend adds the same note an octave higher at a lower level. It makes the drone fuller and easier to hear against a low instrument, and it is the closest thing here to the layered sound of a tanpura. In the app, a Fifth blend adds a perfect fifth tuned as a pure 3:2 ratio rather than the equal-tempered fifth, which is the beatless interval a string or wind player tunes their own fifths against; the Reed and String voices add brighter and denser harmonic stacks for the same reason Warm helps more than Pure.
Why the note never moves
Everything alive in the Warm voice, the harmonics and the slow shimmer, is built around one component that is never detuned and never moves: a sine at exactly the note frequency. The shimmer comes from quiet copies of the harmonic series a few cents either side of it, breathing slowly so the texture never freezes into one fixed beat rate, but the centre stays put. That is the rule that makes a tone this rich still usable as a pitch reference, and it is the same rule the app's drone is built on. Every harmonic is an exact whole-number multiple of the note, too, because a stretched or bell-like series has no single pitch to tune to.
Questions about tuning drones
What is a tuning drone?
Which note should I set the drone to?
What reference pitch should I use?
Should I use the pure or the warm sound?
Can I run this drone and a tuner app at the same time?
Is this tuning drone free and accurate?
The same drone, next to a tuner, on your phone.
Metro Gnome puts a tuning drone in the Tuner tab, sharing the tuner's reference pitch so the two can never disagree, with the Reed and String voices, a pure-fifth blend, and a drift-free metronome to practise over. The needle rests while the drone sounds and returns the moment you stop it. Free on Android, no account, no subscription.
Get it Free on Google PlayUse this on your own site
This drone embeds on any website with one line of HTML, free, with no sign up and no API key. String teachers, choir directors and studio pages are welcome to put it straight onto a lesson or warm-up page rather than sending students elsewhere. Get the embed code.