A frequency sweep plays a continuous tone that gradually changes from low to high frequencies (or vice versa). It helps test the frequency response of speakers, headphones, or your own hearing across the entire audible spectrum — typically from 20 Hz to 20,000 Hz.

Set the mode to Auto Sweep, choose your preferred speed, and click Play. Listen for any distortion, rattling, buzzing, or uneven volume across frequencies. A healthy speaker should produce smooth, clean tones throughout the sweep. Use Left Only / Right Only to test each channel independently.

The average human can hear frequencies from 20 Hz to 20,000 Hz. However, this range shrinks with age — a condition called presbycusis. Most adults over 30 cannot hear above 15–16 kHz, and by age 50 the upper limit often drops to around 12 kHz or lower.

High-frequency hearing loss is natural with age. The hair cells in your inner ear that detect high frequencies are the most fragile and are typically damaged first — by aging, loud noise exposure, or certain medications. If you're over 25 and can't hear above 15 kHz, it's completely normal.

Run a slow frequency sweep and listen carefully. Signs of damage include: buzzing or rattling at certain frequencies, sudden volume drops, distortion (unclean tone), or complete silence in a frequency range. Also test left and right channels separately — a mismatch often indicates a problem.

Sine Wave: The purest tone — a single frequency with no harmonics. Best for clean frequency testing.
Square Wave: Rich in odd harmonics, sounds buzzy. Good for testing transient response.
Sawtooth Wave: Contains all harmonics, bright and aggressive. Reveals distortion easily.
Triangle Wave: Odd harmonics that roll off faster than square waves, smoother sound.

Yes, when used responsibly. Always start at low volume (20–30%) and increase gradually. Avoid prolonged listening at high volumes — especially above 85 dB. High-frequency tones at loud volumes can cause ear fatigue quickly. For speaker testing, moderate volume is sufficient to reveal issues.

Absolutely. This is an excellent tool for headphone testing. Use the Left Only / Right Only channel options to check each earcup independently. Listen for channel imbalance, distortion, or frequency response differences between the two sides.

Low frequencies (below 60 Hz) are often felt as vibration rather than heard as distinct tones. The human ear is less sensitive to very low frequencies, which is why subwoofers exist. At equal volume settings, low frequencies may seem quieter — this is normal and related to the equal-loudness contour of human hearing.

Frequency response describes how accurately a speaker or headphone reproduces each frequency. Ideally, all frequencies should play at the same volume — this is called a "flat" response. In reality, most speakers have peaks and dips. A frequency sweep helps you subjectively identify where your equipment may be boosting or cutting certain frequencies.