Audacity Spectrogram & Frequency Analysis: Find Hum, Noise, Clicks & Resonances
Share
AUDACITY AUDIO ANALYSIS
Audacity Spectrogram & Frequency Analysis: Find Hum, Noise, Clicks & Resonances
A waveform shows level over time. A spectrogram shows how frequency energy changes over time. Audacity can also display waveform and spectrogram together and use Plot Spectrum for closer frequency inspection.
Use waveform when…
- you are locating edits, silence and obvious transient spikes;
- you need timing and level context;
- the problem is visually obvious as a click or abrupt cut.
Use spectrogram when…
- you hear a hum or whistle but cannot locate it easily;
- you want to see persistent high-frequency hiss;
- a click appears as a broadband vertical event;
- you are comparing frequency content across sections;
- restoration needs frequency-specific evidence.
Window-size tradeoff
Audacity notes that spectrogram accuracy involves a tradeoff: smaller windows improve time resolution, while larger windows improve frequency resolution. Choose the view for the question you are asking.
Diagnostic loop
- Hear the problem first.
- Mark the timestamp.
- Switch to spectrogram or multi-view.
- Identify whether the defect is transient, broadband or narrow-frequency.
- Choose the repair tool that matches that evidence.
- Return to listening after repair.
Do not mix by picture. Spectral tools are evidence, not a substitute for listening. A bright-looking spectrum can be correct for one recording and wrong for another.