SonaLab - Real-Time Vocal Analysis Software
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Flat Intonation

音准偏低

SonaLab is a voice analysis and training tool, not a medical device. Symptom detection and scores are for reference only and do not constitute medical advice or diagnosis. Consult a qualified physician for persistent voice discomfort.

Several consecutive notes all sit below pitch — a typical sign of insufficient stretch.

In One Sentence

The hint appears only when several consecutive notes each have a median pitch more than about 25 cents below the target (the nearest equal-tempered note). Judged per note: each note takes the deviation of its vibrato center, and slides, onsets/offsets, and stray bends don't trigger it.

How to Read It

Watch the Pitch chart (True Intonation mode shows cent deviations). The hint appears when the median deviation of several consecutive notes stays negative and each exceeds the threshold; the alert says how many notes in a row and by how many cents at most.

Why Does This Happen?

CauseDescription
Insufficient stretchThe folds don't thin in time and the pitch falls short (most common)
Insufficient breathNot enough subglottal pressure; the pitch sags
Low onsetsApproaching every note from below and stopping there

How to Improve

  • Straight tone: hold the target note and learn your habitual pitch placement
  • Octave slides: slide up lightly and find the feeling of reaching the note without breaking
  • The A4 reference is adjustable in Settings (orchestra habits like 442Hz)
  • Related

  • Pitch chart
  • Weak Stretch (CT)
  • Sharp Intonation