Tone Generator

Tone Generator — Pure, Precise Audio Signals

Generate clean test signals from 20 Hz to 20 kHz directly on your phone: steady tones, noise and sweeps. A minimalist instrument for musicians, sound engineers, students, and anyone who needs a reliable signal source on the go.

TONES
• 20 Hz to 20 000 Hz on a logarithmic slider, with ±1 Hz buttons and direct entry for exact values
• Three waveforms — Sine (pure tone), Square (rich harmonics), Triangle (warm timbre)
• Musical note display — shows the closest note (A4, C♯5, and so on)
• Quick presets for 432, 440, 528 Hz and 1 kHz, plus your own pinned frequencies

NOISE
• White, pink and brown noise, generated continuously — never a looping sample

SWEEPS
• Glide between two frequencies over 5 to 120 seconds
• Linear or logarithmic, one-shot or looping
• The readout follows the signal as it runs

BUILT FOR REAL WORK
• Route the signal to the left speaker, the right, or both — test one channel at a time
• Keep the screen on so a measurement is never cut short
• Auto-stop after 5, 15, 30 or 60 minutes
• Pauses for calls and stops when headphones are unplugged, so a pure tone never lands in your ears at full volume
• Dark and light themes, tablet layout, 14 languages

AUDIO ENGINEERING
• Band-limited synthesis using PolyBLEP and PolyBLAMP — no harsh aliasing artefacts
• The device's native sample rate, so nothing is resampled on the way out
• Waveforms matched for equal loudness: changing shape changes timbre, not level
• Every transition — start, stop, sweep seam — is ramped, so there are no clicks

HEARING SAFETY
Pure tones concentrate all their energy on one frequency and feel deceptively quiet. The app opens with a short safety notice and keeps it one tap away.

This app is not a medical device.

Made by KirsuLab LLC.