Tone Generator
Pure, precise audio tones from 20 Hz to 2 kHz.
About
Tone Generator is a minimalist audio frequency tool for musicians, sound engineers, students, and anyone who needs a reliable signal source on the go. Generate clean, accurate test tones from 20 Hz to 2 kHz directly on your phone.
Features
- Frequency range from 20 Hz to 2 kHz with a logarithmic slider for natural pitch navigation
- Three waveforms — sine (pure tone), square (rich harmonics), triangle (warm timbre)
- Tap-to-edit frequency field for exact values like 432, 440, or 528 Hz
- Quick preset buttons for 432, 440, and 528 Hz
- Musical note display showing the closest note (A4, C♯5, …) for any frequency
- Dark and light themes — the app opens in light by default and remembers your choice
- Haptic feedback on slider movement for tactile precision
- Your last frequency, waveform, and theme are preserved across app launches
Audio engineering
- Band-limited synthesis using PolyBLEP and PolyBLAMP — no harsh aliasing artefacts, even at higher frequencies
- Smooth gain envelopes — no clicks or pops at start, stop, or app suspend
- Continuous-phase frequency changes — slide smoothly without zipper noise
- 44.1 kHz / 16-bit PCM playback through your device's standard media output
Hearing safety
Tone generators can damage hearing more easily than music — a pure continuous tone concentrates acoustic energy on a single frequency, and pure tones feel deceptively quiet. Set device volume to about 20–30% before pressing Play, limit sessions to 15–20 minutes, and be especially careful in the 1–2 kHz range. The app shows this guidance on first launch and keeps it one tap away behind the info icon.