Audio Frequency Sweep Test (20 Hz – 20,000 Hz)
Test the entire audible spectrum to evaluate your speaker's low-end bass extension, midrange linearity, and high-frequency limits without installing any software.
Frequency Sweep — 20 Hz to 20 kHz
Starts at a conservative volume. Listen for frequencies where the sound drops out, distorts, or rattles — those indicate response limitations.
Channel Tests
Wireless audio tip: If sound plays in both ears on single-channel tests, verify that OS Mono Audio is off and your headset is not set to hands-free call mode. See Bluetooth guide.
Phase / Polarity Test
Play the normal tone first, then the inverted one. With correct wiring the inverted version should sound noticeably thinner, quieter, or harder to locate, because the two channels partially cancel.
Bass / Sub-bass Test — 40 Hz
If you hear nothing, your speakers may not reproduce sub-bass frequencies — this is normal for laptop speakers and small earbuds.
Rattle / Resonance Test
A 60 Hz tone drives low-frequency resonance. A rattle or buzz may indicate loose components or debris in the driver enclosure.
Channel Balance Check
Both tones play at exactly the same level. Compare how loud each side sounds — a clear difference suggests channel imbalance rather than a fully dead channel.
How to run an audio frequency sweep in 3 steps
- Start at a moderate listening level: Keep system volume around 40–50% to prevent driver damage during high-energy bass and treble sweeps.
- Trigger the Sine Wave Sweep: Listen as the tone smoothly climbs from 20 Hz (a mechanical vibration) through warm mid-tones up to a high-pitched 20 kHz whistle.
- Note volume dropouts and resonances: Listen for sudden dips in loudness (frequency nulls) or harsh buzzing peaks (room resonances).
The Audible Audio Spectrum Explained
Sub-Bass (20 Hz – 60 Hz)
Felt rather than heard. Laptop and phone speakers produce zero sound here; only dedicated subwoofers and studio monitors can reproduce these deep frequencies.
Mid-Bass (60 Hz – 250 Hz)
Provides warmth, punch, and rhythm. Kick drums and basslines live here. Cabinet rattles and loose components typically buzz in this range.
Midrange (250 Hz – 4,000 Hz)
The core of human speech, guitar, and piano. Smooth response across the midrange ensures clear call dialogue and natural vocal playback.
Treble & Air (4,000 Hz – 20,000 Hz)
Cymbals, acoustic sparkle, and high consonants ('s' and 't'). Human hearing in adults naturally declines above 15,000 Hz.
Quick answers
Frequently asked questions
What frequency range can human ears hear?
Healthy human hearing spans from roughly 20 Hz (very deep bass rumble) to 20,000 Hz (high treble sizzle). High-frequency hearing naturally declines with age; adults over 30 often cannot hear frequencies above 15,000–16,000 Hz.
Why does the frequency sweep sound silent below 100 Hz on my laptop?
Laptop speakers and phone speakers have tiny diaphragms (10–20 mm) that physically cannot move enough air to produce sub-bass below 100 Hz. The audio is playing, but the hardware cannot reproduce it.
Can high-frequency sweep tones damage speakers?
Sweep tones played at moderate volumes are completely safe. However, playing sustained high-frequency tones (>10 kHz) or deep sub-bass (<40 Hz) at maximum amplifier volume can overheat speaker voice coils. Always test at a moderate listening level.