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Best Harmonica Tuner? Free Strobe to Check Richter Reeds
Tuning a harmonica means checking reeds
Unlike a guitar, you do not normally tune a harmonica at the gig - the reeds are fixed at the factory and retuning requires reed work. But reeds drift flat with age, saliva buildup, and hard playing, and a single flat draw reed ruins bends and chords. The best harmonica tuner is the one that tells you quickly which reed has drifted, so you know whether to clean, retune, or replace the harp.
Richter tuning: 20 reeds per key
A standard 10-hole diatonic uses Richter tuning: two reeds per hole (blow and draw), 20 reeds total. In key of C, the blow reeds are C4, E4, G4, C5, E5, G5, C6, E6, G6, C7 (a C major chord across the harp) and the draw reeds are D4, G4, B4, D5, F5, A5, B5, D6, F6, A6. Holes 4–7 give the full C major scale. StroboPro loads all 20 as targets so you can check each one.
Blow and draw each reed cleanly
Isolate one reed at a time: blow gently and steadily into a single hole for the blow reed, then draw for the draw reed. Avoid bends - you want the natural pitch. The strobe's harmonic rings show whether the reed sits on pitch or has gone flat; a reed that reads several cents flat across a few checks is a candidate for retune or replacement.
How to check a harmonica with StroboPro
- Open the harmonica tuning - tap the Tap to Tune button (the one with the microphone) and allow microphone access.
- Blow gently into hole 1 and read the strobe; the target note loads automatically.
- Move through each hole, checking blow then draw, one reed at a time.
- Reeds that read consistently flat are drifting - note which holes.
- Use the results to decide between cleaning, reed adjustment, or a new harp.
Related guides
Frequently asked questions
What reeds does a 10-hole C harmonica have?
Richter tuning gives 20 reeds: blow reeds C4, E4, G4, C5, E5, G5, C6, E6, G6, C7 and draw reeds D4, G4, B4, D5, F5, A5, B5, D6, F6, A6. StroboPro ships these as a preset so you can check each one. Open it directly: [harmonica Richter C tuning](https://strobopro.se/preset/harmonica/10-hole/richter-c).
Why has my harmonica started sounding bad?
Usually a reed has drifted flat from age, saliva, or hard playing - especially a draw reed that no longer bends cleanly. Check each reed with a strobe tuner; a reed reading several cents flat is the culprit and the harp likely needs reed work or replacement.
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Published by Applicaudia, the maker of StroboPro. The 0.1-cent figure describes the tuner's display resolution, not a lab-measured accuracy specification. Frequency values are equal-temperament approximations; harmonica reeds are often tuned slightly to player preference.
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