ToneScope vs Spectrum Analyzer+ Audio FFT

ToneScope helps you see and understand sound in real time. ToneScope transforms complex audio into visual representations that are easy to interpret. Whether you're exploring music, investigating environmental noise, or simply curious about the sounds around you, ToneScope makes sound easier to understand. It uses a multirate FFT approach to achieve high frequency resolution at low frequencies while remaining efficient for real-time use on iOS. Users can analyze audio in real time or record sound locally and analyze it later. All processing is performed entirely on-device. Optional audio recordings are saved locally under user control. No data is transmitted, uploaded, or collected. Designed and developed by Newton Niu.

Spectrum Analyzer+ Audio FFT shows the live frequency spectrum of any sound your iPhone microphone hears, then lets you capture a 5-second average and read the result: the strongest frequency in Hz, the top components and where the energy sits. ▶ See the spectrum live • 32 bands from 20 Hz to 20 kHz, computed with a 2048-point FFT • Four views: Bars with peak hold, Line, Waterfall and Spectrogram • Peak frequency and peak level update as you listen • Min / Max traces in the Bars view, tap a bar for a cursor readout, freeze the display to study it • Adjustable dB range from 30 to 120 dB ▶ Capture 5 seconds, get an answer Tap Capture 5 s under the graph and hold the sound steady. The app power-averages the spectrum over five seconds and shows a result card: • Strongest component in Hz, with the musical note and cents in Voice mode • Up to three top components with their levels • Share of the detected energy in the low, mid and high part of the selected range • Strongest band level and the FFT resolution of the measurement If the sound is too quiet in that range, the card says so instead of inventing a peak. ▶ Compare before and after Save a capture as a reference (up to 10). Make a change — move a speaker, add treatment, adjust a machine — capture again in the same mode and the card shows the average band-level difference in dB. References can also be overlaid on the live spectrum. ▶ Pick the job • Voice: 80–4000 Hz, shows the note of the strongest pitch • Machine: 20–2000 Hz, looks for 50/60 Hz mains hum and its harmonics • Room: 20–500 Hz, the low end where room modes build up ▶ Export and share • Export a CSV of the live spectrum or of a 5-second capture • Share a short text summary of a capture ▶ Extras • Calibration offset from −20 to +20 dB in 0.5 dB steps to line up with a reference meter • Pink noise generator, unlocked for 24 hours by watching a short ad • Interface in 30 languages ▶ Good to know Levels are relative to the microphone's full scale (dBFS). A phone microphone is not a certified sound level meter, so use the numbers to find frequencies and compare changes, not for compliance measurements. Audio is analysed in memory while you listen and is not saved as a recording. For musicians checking a tone, home studio and hi-fi owners chasing a boomy note, and anyone tracking down a hum from a fridge, fan or transformer.