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Free Hz Generator1 Hz – 20 kHz Lab

Acoustic & Hearing Safety Notice

Important

Protect your ears and audio hardware: Continuous high-volume exposure to pure sine tones can cause permanent hearing damage or blow out speaker voice coils. Human ears have reduced sensitivity below 20 Hz and above 10,000 Hz.

💡 Rule of thumb: Calibrate your device volume using a 1,000 Hz tone at a soft, comfortable level. Do not raise the volume if inaudible at extreme frequencies.
🧪 Audio Engineering & Acoustic Calibration Lab

Audio Reference & Noise Calibration

Industry standard 1 kHz alignment reference levels, pink/white noise generators for RTA acoustic tuning, and harmonic distortion listening benchmarks.

01

1 kHz dBFS Alignment Reference Tones

Exact digital gain calibration standards.

Calibrate mixers, audio interfaces, and digital audio workstations (DAWs). -18 dBFS and -20 dBFS represent standard broadcast and film alignment levels (+4 dBu / 0 VU).

02

Acoustic Noise Lab (RTA Room Tuning)

Generate un-correlated stereo pink and white noise.

Pink Noise (1/f) contains equal energy per octave, making it the industry standard for calibrating studio room acoustics and Real-Time Spectrum Analyzers (RTA).

Harmonic Distortion & THD Ear Training

Listen to how subtle clipping and 3rd harmonics alter a pure 440 Hz sine tone: