Modal Frequency Reader — Tap Tone Viewer

A simple, accurate way to inspect tap tones and short clips. View the waveform, see the FFT, and identify resonant peaks with note and cents readouts.

How to use

Tap tones & frequencies

Tap tones reveal how a plate or box behaves. The waveform shows the impact; the FFT shows the resonances it excites.

Recording a tap

  • Place the mic 75–150 mm from the plate or guitar; mute strings on a box.
  • Tap near center for monopole content; tap near an edge to highlight cross/long modes.
  • Record a short, clean tap—or load a WAV file.

Zoom the waveform to isolate the tap. The FFT automatically follows that selection. Hover over the FFT to see frequency, level, note, and cents. Click to add a marker.

Accuracy tips

  • Tap firmly, but avoid clipping your preamp.
  • Move the mic a few centimeters if peaks look smeared.
  • A quieter room reduces low-frequency noise.

Waveform & FFT

Waveform navigator

1.5 s • 44.1 kHz

FFT + Note Grid

hann window • tone gen: Off
-- Hz -- dB Note: --
Waveform navigator with time zoom; FFT with note grid; basic peak markers with frequency, level, and pitch info.

Selected frequencies

Label Frequency (Hz) dB Note / cents
Click the FFT to add a marker. Hover updates the tone generator and shows note/cents.

Detected modes & wolf risk

Auto-picked peaks within your Air / Top / Back bands.