How to Read a Spectrogram: Your Voice's 'X-Ray'

What Is a Spectrogram?

If pitch detection is like taking your voice's "temperature," a spectrogram is like an "X-ray" — it reveals all the internal details of your sound.

A spectrogram is a three-dimensional chart: the horizontal axis is time, the vertical axis is frequency (pitch), and color intensity represents energy. Warm colors (red/yellow) mean strong energy; cool colors (blue/black) mean weak energy.

How to Read a Spectrogram

Horizontal Stripes = Harmonics

When you sing a steady note, you'll see rows of bright horizontal lines. The bottom line is the fundamental frequency (the note you're singing), and each line above is a harmonic. More and brighter harmonics mean a richer, fuller sound.

Stripe Spacing = Pitch

The wider the spacing between stripes, the higher the pitch. When you slide from low to high, you can see the spacing gradually increase.

Fuzzy "Fog" = Breathiness

If the spectrogram has blurry areas without clear stripes, like a layer of fog, this usually means breathiness — the vocal cords aren't closing tightly enough, and airflow noise is mixing into the sound.

Bright High-Frequency Areas = Projection

If there's a noticeable bright band in the 2000-4000 Hz region, your voice has good projection power (the singer's formant).

What Can a Spectrogram Tell You?

How SonaLab Helps

SonaLab's Spectrogram shows your voice's spectral information in real time. Watch harmonics shift while you sing, or dig into the details during recording playback. It works best alongside other charts — spot "fog" on the spectrogram, then switch to Breathiness Detection to confirm whether it's a closure issue.