Install this app on your device for quick access — it works offline and nothing ever leaves your device.
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Vowel Chart
Plots your live F1/F2 (the same two formants shown in the HUD) as a moving dot. Two reference modes: "IPA vowels" (IPA vowels, Hillenbrand et al. 1995) shows which vowel shape your tongue/jaw are making; "M/F clusters" instead shows your position against masculine- and feminine-typical corner-vowel averages (Peterson & Barney 1952 / Hillenbrand et al. 1995) — population averages with substantial individual overlap, not a category your voice must fall into. Approximate, not diagnostic either way.
Press Start, sustain an /i/ ("ee") vowel, then tap Calibrate — Hirsch's technique carries that tongue position's F2 across other vowels to brighten resonance consistently. The dashed line on the chart above shows your calibrated F2.
Not calibrated yet
Scroll or pinch to zoom, drag to pan, double-click to reset.
Drag to rotate, scroll to zoom.
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Welcome
A few optional things to set up before you start — everything here can be changed
anytime in Settings, and nothing here ever leaves your device.
1. Target range
Pick a pitch range to aim for — unlocks the "% in target", Target Δ, and
Acoustic Proximity target-matching features.
2. Recording
Stored locally in your browser only — nothing is uploaded anywhere. Off by default.
3. Microphone
Pick which input to use — this also sets the main Microphone selector.
4. Background noise calibration
Stay quiet for a few seconds so we can measure your room/mic's actual noise floor and
set it automatically, instead of guessing with a slider.