Spectrum Analyzer: Audio FFT

Spectrum Analyzer turns your phone microphone into a live audio FFT analyzer. Watch the frequency spectrum of any sound, then capture a 5-second average to see exactly which frequency is the strongest and how the energy is spread. WHAT YOU SEE LIVE • 32 frequency bands from 20 Hz to 20 kHz (2048-point FFT) • Bars with peak hold, Line, Waterfall and Spectrogram views • Peak frequency in Hz and peak level in dB • Min / Max traces, cursor readout on any bar, freeze • dB range adjustable from 30 to 120 dB THE 5-SECOND CAPTURE Tap Capture 5 s and keep the sound steady. You get a result card with: • The strongest component in Hz (plus note and cents in Voice mode) • The top three components and their levels • How the detected energy splits between low, mid and high in the chosen range • The strongest band level and the FFT resolution Too quiet in the range? The card tells you, instead of showing a made-up peak. BEFORE / AFTER Save a capture as a reference, change something, capture again in the same mode and read the average dB difference. Keep up to 10 references and overlay one on the live graph. THREE MODES • Voice 80–4000 Hz with note name • Machine 20–2000 Hz with 50/60 Hz mains hum and harmonics • Room 20–500 Hz for low-frequency room modes MORE • CSV export of the live spectrum or a capture, text summary to share • Calibration offset −20 to +20 dB (0.5 dB steps) • Pink noise generator, unlocked for 24 hours with a short ad • 30 languages HONEST LIMITS Levels are dBFS, relative to the microphone's full scale. A phone is not a certified sound level meter: use it to find frequencies and compare changes. Sound is analysed in memory and never saved as a recording. Useful for tuning an instrument by ear, finding a boomy note in a room, checking a speaker, or tracking down a hum from a fan, fridge or transformer.

The rating request no longer appears when the app starts. It now appears at most once, about 4 seconds after your third finished “Capture 5 s” result since this update, and only if you have not touched the screen or left the app since, no capture is running and no automatic full-screen ad was shown in the last 30 seconds; otherwise it waits for a later capture. “Review” in the menu is unchanged.