Tone Generator: Hz & Noise

Any frequency, clean and precise. Every feature free. Tone Generator: Hz & Noise plays pure test tones, five noise colours and frequency sweeps through a native audio engine built for clean sound: no clicks when you change a value, no aliasing on square and sawtooth waves, no distortion at full volume. For speaker and subwoofer tests, room and audio calibration, tuning by ear, hearing checks, electronics and science lessons. TONE • From 1 Hz to 22 kHz in steps of 0.01 Hz. • Sine, square, triangle and sawtooth. Square, triangle and sawtooth are band-limited, so high tones stay clean. • A large logarithmic dial: turn the inner wheel for smooth changes (one turn is an octave), drag the outer ring to jump anywhere. • Fine steps: ÷2 and ×2 (octaves), ±1 Hz and ±0.1 Hz, or tap the number and type it. • Note mode: pick a note and octave, step by semitones and cents, with A4 adjustable from 415 to 466 Hz. Note names in letters, German (H) or Do Re Mi. • Every change glides smoothly, without clicks or pops. NOISE • White, pink, brown, blue and violet noise, all at the same level, for speaker tests, masking, sleep and focus. SWEEP • From one frequency to another in 5 seconds to 10 minutes, linear or logarithmic, once or in a loop, with a live graph and the current frequency. TEST TOOLS • Left, right or both channels, balance, and polarity inversion on the right channel to check that your speakers are wired in phase. • Extra tones: add up to three tones for beats and chords, with the beat frequency shown. • Bursts: pulse the sound with a period from 20 ms to 5 s and an adjustable duty cycle. • Sleep timer, from 1 minute to 2 hours. • A small oscilloscope draws the real generated wave. PRESETS AND FAVOURITES • A4 440, 432 and 442 Hz, 1 kHz calibration, 60 Hz sub test, 50 and 60 Hz mains hum, middle C, and hearing checks at 8, 12, 15 and 17 kHz. • Save your own tones as favourites and recall them with one tap. SAFE FOR EARS AND SPEAKERS • Every start fades in from silence. A volume limit you choose, and a warning before a loud first play. • A note tells you when a phone speaker may not reproduce a very low or very high tone. • The sound stops when headphones are unplugged or a call comes in. FREE AND PRIVATE No ads, no in-app purchases, no subscription, no account. Works offline, no microphone, no data collected: your favourites stay on your device. This app is not a medical device: the hearing checks are not a hearing test. Dark and light theme, 71 languages. Made by FELICE MARRA / MUSIC STUDIOS.