Analyzing Audio Frequency Spectrum
This frequency analyzer displays the frequency content of your audio as a spectrum graph. Choose FFT size (1024 to 8192) for different resolution levels. The graph shows magnitude (loudness) at each frequency from 20 Hz to 20 kHz.
FFT (Fast Fourier Transform) breaks down the audio into its component frequencies. Higher FFT sizes give finer frequency resolution but coarser time resolution. The result is a frequency spectrum showing which frequencies are present and how strong they are.
Practical Applications
- Musicians who identify problematic frequencies in a mix. They see a spike at 400 Hz and know to cut that range.
- Audio diagnosticians spotting excessive low-end rumble or harsh high frequencies.
- Producers checking if their mix has balanced frequency content across the spectrum.
- Audio engineers verifying that a high-pass filter is working by seeing the low frequencies disappear.
- Educators creating content about audio who use frequency spectrum visualizations to demonstrate concepts.
What to Know Before Using It
- The spectrum shows the entire file averaged together, not a real-time display. You can't see how frequencies change over time.
- FFT size affects resolution: 1024 gives coarse frequency bins; 8192 gives fine detail but requires more processing.
- The graph uses a logarithmic frequency scale (like human hearing). Low frequencies are spread out; high frequencies are compressed.
- Magnitude is shown in dB. Higher lines = louder at that frequency. The scale typically ranges from -100 dB to -20 dB.
- This is an analysis tool, not a fix. Use the equalizer to actually change frequency content.
FAQ
- What does the frequency spectrum show?
- Which frequencies are present in your audio and how loud each one is. Peaks show dominant frequencies; valleys show absent ones.
- What FFT size should I use?
- 2048 (default) works for most purposes. Use 1024 for quick overviews; 4096 or 8192 for detailed analysis.
- What's a healthy frequency spectrum?
- Generally, a gentle downward slope from low to high frequencies. Excessive peaks indicate resonances; big dips indicate missing content.
- Can I see how frequencies change over time?
- No—this shows a static spectrum of the entire file. For time-varying spectra (spectrograms), you need dedicated analysis software.
- Does this show stereo frequency content?
- No—the analysis is mono (combined channels). Stereo spectrum analysis would need separate left/right displays.
- What frequencies should I look for?
- 20-80 Hz: sub-bass. 80-250 Hz: bass. 250-500 Hz: low mids. 500 Hz-2 kHz: mids. 2-4 kHz: upper mids. 4-20 kHz: highs/treble.