Pure low end on demand: sine tones from 10 to 250 Hz with presets at the frequencies that matter - subwoofer checks, room boom hunting, and bass reference notes. Use headphones or real speakers; laptops cannot reproduce most of this range.
Careful with the volume: low frequencies at high level stress drivers hard - and rattles you hear may be your room, not the speaker.
Below roughly 30 Hz you feel more than hear - a clean system produces pressure without buzz. Tones that boom at one frequency and vanish at another are your room speaking, not the speaker: predict those spots with the room mode calculator. For the guided bass workup use the subwoofer test, and for full-range work the main tone generator covers 20 Hz to 20 kHz.
Testing the bottom octaves: how low a subwoofer or speaker genuinely reaches, where a room booms or cancels, whether cabinets and furniture rattle, and providing reference pitches for bass instruments (low E on a bass guitar is 41.2 Hz).
Three possibilities in order: your playback hardware cannot reproduce it (laptop speakers stop around 200-300 Hz, small earbuds around 40-60 Hz), the volume is below your hearing threshold (sensitivity drops steeply at the extremes), or the tone is playing as feelable pressure rather than audible pitch - 20 Hz sits at the official edge of hearing.
Sweep the 20-80 Hz range rather than trusting one tone: 40-60 Hz shows the power region of the sub, 25-30 Hz separates real subwoofers from pretenders, and 80 Hz checks the crossover handoff to your main speakers.
At sensible volumes, no. At high volume, low frequencies stress equipment (port chuffing, driver bottoming) before they harm hearing - but sustained loud exposure at any frequency damages hearing, so keep sessions moderate.
Generate single tones with precise frequency control. Perfect for quick audio testing and tuning.
Play multiple frequencies simultaneously with independent volume and panning controls.
Create linear or exponential frequency sweeps for speaker testing and room acoustics analysis.
Generate binaural beats for meditation, focus, and relaxation. Requires headphones for proper effect.
Generate telephone dial pad tones (Dual Tone Multi Frequency). Interactive touch-tone dial pad.
Professional metronome with tap tempo, time signatures, subdivisions, and tempo trainer for musicians.
Tap along to any song to find its tempo in beats per minute. Includes tempo markings reference.
Hear major, minor, diminished, and seventh chords in every key. Block chords or arpeggios.
Hear classic progressions like I-V-vi-IV and 12-bar blues in any key at any tempo.
Free browser piano with 3 octaves, note names, and computer keyboard support.
Generate white, pink, and brown noise for sleep, focus, tinnitus relief, and speaker burn-in.
Reference tuning notes for guitar, bass, ukulele, violin, cello, and more at concert pitch (A440).
Test your subwoofer with a 60-second frequency sweep (150Hz-1Hz) and individual bass test tones.
Test your hearing range from 8kHz to 20kHz. Find your hearing age and compare with averages.
Ancient healing tones including 528Hz (DNA repair). For meditation, chakra activation, and spiritual healing.
Test stereo balance with panning control and left/right channel testing. Perfect for speaker setup.
Check speaker wiring polarity by comparing in-phase and out-of-phase test signals.
Measure your Bluetooth or system audio delay in milliseconds with a click-and-flash sync test.
Real-time frequency analysis of your microphone input with a live log-frequency display.
Measure approximate sound levels with your microphone - live dB with min/avg/max tracking.
Check your microphone in seconds: live waveform, level meter, and record-and-playback check.
Learn to recognize musical intervals by ear with quiz mode, score tracking, and song mnemonics.
Chromatic pitch pipe with all 12 notes across 3 octaves. Perfect for singers, choirs, and a cappella groups.
Experience the auditory illusion of an infinitely ascending or descending tone. Mind-bending psychoacoustic phenomenon.
Can you hear the mosquito tone? High-frequency test (15-20kHz) that only young people can hear. Find your hearing age!
Create relaxing ambient soundscapes with singing bowls, nature sounds, and binaural beats.
Three sound modes to clean a muffled speaker: 165 Hz water eject, dust-shaking sweeps, and vibration.
Push water out of a wet phone or watch speaker with a pulsed 165 Hz tone - the same method Apple Watch uses.
Adjustable high-frequency whistle (8-22 kHz) for dog training - clearly audible to dogs, silent to most adults.
Rhythmic pulsed tones across delta to gamma ranges. Stronger than binaural beats and works without headphones.
Name 12 random notes with no reference tone and find out if you have absolute pitch or great pitch memory.
Sing your lowest and highest notes and get your range plus voice type - bass to soprano. Mic-based, nothing uploaded.
Find the highest frequency you can hear (8-20 kHz) and see how old your ears test. Takes one minute.
Instant karaoke via center-channel cancellation - free, unlimited, and processed locally.
Record from your microphone and download as WAV - no signup, nothing uploaded.
Normalize any file to a LUFS target with true-peak protection instead of silent clipping.
16-step beat maker with synthesized 808-style drums, swing, and shareable pattern links.
Drop a file and get integrated LUFS, true peak, RMS, and a waveform - measured locally, nothing uploaded.
Microphone tuner with a cents needle - play any note on any instrument and tune to ±5 cents.
Five-minute headphone checkup: channels, wiring polarity, bass and treble reach, and driver distortion.
Send noise to each 5.1 channel - fronts, center, surrounds, and subwoofer - and catch swapped or dead speakers.