What it is

A pocket spectrum analyzer built like a vintage hi‑fi rack. Point it at any sound, watch the meters, then capture 30 seconds and mangle the loop with EQ, tape‑speed warping, and dub echo. Save the result as a WAV.

1. Pick a source

Mic listens through the microphone: hold it up to a speaker, an instrument, or the room. File plays an audio file from your device. Tab captures a browser tab's audio, and works on desktop Chrome or Edge only, not on phones.

Tap Listen to start (it reads Play for a file). Tap again to stop. On a phone the mic takes over the audio session, so pause other music apps first, or use File for a track saved on the same phone.

2. Read the display

The button at the bottom‑left cycles six views: Bars is a 31‑band LED spectrum. Radar draws the spectrum as concentric rings, bass at the centre out to treble at the rim. Scope is the raw waveform. Multi splits the sound into low, mid, and high lanes and scrolls each like a multitrack. DNA reads the track's fingerprint: tempo, energy, brightness, density, punch, and tone. Spectro is a scrolling spectrogram: frequency runs bottom to top, time scrolls right to left, and color is intensity, so harmonics stack as stripes and beats fall as vertical streaks.

The three windows under the display show level, peak hold, and the dominant frequency with its musical note.

3. Capture a loop

With something playing, tap Record 30s. It captures up to 30 seconds, or tap again to stop early, then normalizes the clip. Tap Loop to play it back on repeat. Everything below now works on that loop.

4. Shape it

The Analyze / EQ / Warp row switches what the display does. In EQ, drag your finger across the display to draw a 31‑band graphic EQ curve; the bottom‑left button becomes Flatten to reset it. In Warp, drag up to speed a moment up and down to slow it, tape‑style, changing pitch with speed; that button becomes Unwarp.

The Echo sliders add dub delay: Echo time sets the delay, Repeats sets how long it feeds back, and Echo mix blends it in. Repeats darken each pass like real tape. Display gain only changes how hot the meters read, not the sound.

5. Save it

Tap Save WAV to render the warped, EQ'd, echoed loop to a 16‑bit WAV. On a phone the share sheet opens so you can Save to Files; on a computer it downloads.

Tips

Add it to your home screen to run it full‑screen like an app. The screen stays awake while it's listening or looping. If the mic won't grant permission in a home‑screen app, open it in the browser once, allow the mic, then re‑add it.