Is it possible to use a standard 440 Hz digital tuner to emulate a 415 Hz tuner, even if it doesn't explicitly support setting the A4 frequency?

I'm learning to play the viol, and I can't find a good 415 tuner and I'm not skilled enough to tune by ear. I've tried a dozen digital tuning apps for Android, but most don't support setting A4, and the few that do still don't seem to work well for the viol's range.

However, doesn't 415 Hz exactly correspond to a step down in the 440 scale? If a string is, say, D2 at 440, would the effective 415 Hz note be C# at 440? So if I just target a step down for all my notes with my regular tuner, would that work without needing a 415 tuner?

  • 1
    Why try to emulate, when you can buy a tuner which gives the exact Hz anyway?
    – Tim
    Commented Oct 14, 2023 at 7:45
  • 1
    Yes, tuning your strings to the notes a semitone “too low” according to a 440 tuner works perfectly. I.e. 440 A flat = 415 A, 440 D Flat = 415 D etc. But tuning apps that let you adjust the pitch should be a dime a dozen, I’m a little surprised you can’t find any. Are you perhaps only considering free apps? There a few rather good ones that are cheap (below 10$) but not free.
    – 11684
    Commented Oct 14, 2023 at 9:27
  • Strictly speaking, in concert pitch with A = 440 Hz, an equal-tempered G#/Ab = 440×2^-1/12 ≈ 415.3047 Hz.  So tuning to concert G#/Ab should be close enough to 415 Hz for most purposes.
    – gidds
    Commented Oct 14, 2023 at 10:21
  • 1
    Pedantically, it would be off by (if I did my math right) about 1.27 cents. Which is imperceptible to almost everyone; but in the answers so far people are talking about how performers don't tune their fifths to equal temperament - which is only about 2 cents off. Commented Oct 14, 2023 at 21:49
  • 1
    How precisely are you tuning? Are you trying to set a particular temperament or just tune the fourths pure?
    – phoog
    Commented Oct 16, 2023 at 8:14

3 Answers 3


String instruments usually tune by ear, based on a reference pitch for one of the strings (in most orchestral and chamber music settings, this will be the A, whether at 415, 440 or any other reference). Given that much music written for viols predates the widespread use of equal temperament, and that even in modern contexts pure fifths are preferred (violinists do not always, or even usually, tune their strings to equal temperament, see here) - this is a skill you should definitively work on. Exception, of course, if you need to play chamber music with a keyboard instrument tuned in equal temperament, in which case tuning to match that instrument might be best for ensemble playing (though this is something that can also be and is usually done by ear, since viols, like other string instruments and unlike keyboards, may adjust the exact temperament for each note).

That aside, however, a simple solution to your problem, in the meantime, would be to use a piano (or a digital piano app, of which there exist plenty) or other such instrument (organ, ...) and play a G#/Ab (whose frequency will be almost exactly 415 Hz, if the A is 440) instead.

Some "guitar" tuning apps also offer you the possibility to tune with any pitch, so you could employ the same process as above using those.

  • 1
    Fretted instruments were tuned in (something very close to) equal temperament from the 1500s. But viols typically play with harpsichords that are not tuned in equal temperament, so the fifths will be rather more than 2 cents smaller than pure. Viols are tuned in fourths with a major third, similar to a guitar, so the fourths may be a bit wider than pure -- and wider than equal -- and the major third definitely wider than pure but smaller than equal.
    – phoog
    Commented Oct 16, 2023 at 8:10
  • I did specifically write about "the widespread use" of equal temperament.
    – AlexJ
    Commented Oct 16, 2023 at 14:25

Since 415 Hz is a G# in A=440 tuning (to the nearest whole number) if you use your tuner and tune your Bb note to A=440 your A will be 415 Hz provided the instrument plays in tune with itself. At that point you can tune the other strings to the pitch that is its neighbor a semitone higher, so whatever the open string pitch is tune the first fret to that pitch. Your D string should be tuned to D at the first fret. Your C string should be tuned to C at the first fret, etc.

Another option is to get a chromatic tuner that allows has a setting to tune a semitone flat, which is sometimes done by rock or blues guitarists and bassists. If you use the flat tuning function it will basically give you A=415 Hz.

There also are some tuners that go down to a reference of 415 Hz for A4. Some Snark models can do that, maybe others.

  • Korg also make a range of tuners that can be calibrated down to 415 Hz
    – kiwiron
    Commented Oct 14, 2023 at 19:13
  • "At that point you can tune the other strings to the one you tuned as a reference": OP says "I'm not skilled enough to tune by ear." The desire is for a tuner that can measure the pitch of each string.
    – phoog
    Commented Oct 16, 2023 at 8:02
  • @phoog You’re right, I will adjust my answer to reflect that. Commented Oct 16, 2023 at 16:40

Simple question, simple answer. Yes, if A = 440 G♯ = (very near enough) 415. What you suggest will be fine.

  • What does this answer add that is not already covered in both previous ones?
    – AlexJ
    Commented Oct 17, 2023 at 13:20
  • Nothing. It rather subtracts a load of unnecessary waffle.
    – Laurence
    Commented Oct 17, 2023 at 15:44
  • Given that the OP is "learning to play the viol", giving some additional advice and detailing it beyond a mere mathematical-equation-like "G# (440) = A (415)" is certainly not "unnecessary waffle".
    – AlexJ
    Commented Oct 18, 2023 at 1:11

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.