Bass Test Online — 30–200 Hz Tones

A bass test answers one deceptively simple question: where does your system’s low-end output actually stop? This page plays discrete sine tones at 30, 40, 50, 60, 80, 100, 150, and 200 Hz, then runs a 30–250 Hz logarithmic sweep with a live frequency readout, so you can separate true extension from distortion, and speaker limits from room behavior. Everything is generated and played live in your browser; nothing is uploaded or recorded.

How to use it

1. Use the right transducer. Over-ear headphones or full-range speakers with a subwoofer will show you real results. Phone loudspeakers and thin laptop speakers are physically incapable below roughly 150–300 Hz, so testing bass on them measures the speaker’s roll-off, not the audio.
2. Start at 20–30% system volume. Low-frequency energy moves a lot of air, and level that sounds polite at 1 kHz is physically aggressive at 40 Hz. Raise volume only until the tone is comfortably audible.
3. Play the presets upward from 30 Hz, holding each for five to ten seconds. At each frequency, note whether you hear a definite pitch, feel pressure on your chest or eardrums, hear a buzz, or hear nothing.
4. Mark your clean extension limit: the lowest preset that produces steady output without buzzing, crackle, or port noise. That limit belongs to the speaker (or the room), not to your hearing.
5. Run the 30–250 Hz sweep after the presets. Its logarithmic ramp gives each octave roughly equal listening time (about 4.5 seconds per octave across the 14-second run), with the current frequency printed as it moves.
6. Walk the room while the sweep repeats. Stand at the seat, then move a meter left, right, and forward. Note which booms and dropouts move with you and which stay bolted to the floor.

What you are listening for

Pitch versus pressure. Below about 40–60 Hz the ear’s sensitivity falls off steeply; the ISO 226 equal-loudness data put the 40-phon contour some 25–30 dB below its 1 kHz reference at 35–40 Hz, meaning the tone must carry vastly more acoustic energy to sound equally loud. The 30 Hz preset is often felt as air movement, chest pressure, or a rattling window before it is heard as a tone. Judge the bottom presets by output behavior, not by loudness.

The harmonic illusion. A small speaker that “makes” 30 Hz is frequently lying: the cone cannot complete 11-meter wavelengths at useful amplitude, so what you hear is 2nd- and 3rd-order distortion at 60 and 90 Hz. Tell-tale sign: the sound has a definite, octave-too-high pitch while the cone is straining in slow, large excursions. Clean systems below their limit get quieter and buzzier; dishonest ones just get distorted.

Tight versus boomy. The 60–120 Hz region reveals decay: after each sweep pass or punchy preset, does the room stop immediately or hang with a one-two second hum? Ringing marks an excited room mode or an overdriven port.

Musical anchors make the frequencies concrete. The lowest string of a 4-string bass guitar is E1 at 41.2 Hz; a 5-string’s low B0 is 30.9 Hz; a kick drum’s fundamental typically sits between 40 and 80 Hz; the guitar’s low E is 82.4 Hz; bass-reflex tunings commonly land at 35–45 Hz. Your presets are these instruments’ actual working range.

Bass frequency reference

Frequency	Wavelength in air (343 m/s)	Musical / system anchor	What the preset exposes
30 Hz	11.4 m	5-string bass low B0, synth sub	Subwoofer-only territory; first hard limit
41 Hz	8.3 m	Bass guitar low E (E1)	Small-driver distortion onset
50–60 Hz	6.9–5.7 m	Kick fundamentals, 50 Hz mains hum region	Room boom, port noise
82 Hz	4.2 m	Guitar low E, bass upper fundamentals	Enclosure coloring, mode excitation
100 Hz	3.4 m	Bass-to-kick blend zone	Muddy midbass, boundary gain
120 Hz	2.9 m	LFE upper limit, common crossover region	Sub/satellite integration gap
150–200 Hz	2.3–1.7 m	Upper bass, punch region	Boxy room response, thin speaker bleed

Room behavior follows from the same physics: a rectangular room reinforces frequencies whose half-wavelengths fit its dimensions, so a 6 m room has an axial mode at 343 ÷ (2 × 6) ≈ 28.6 Hz and another near 57 Hz. That is why the 30 Hz preset can be thunderous in one seat and inaudible two meters away.

Sweep versus presets: why both

Discrete presets isolate one variable: at 50 Hz, any buzz is happening at 50 Hz. The sweep instead shows transitions, where output fades in, where a mode blooms, where a crossover hole swallows two octaves’ worth of energy in a smooth dip. Logarithmic sweeps matter musically because pitch perception is multiplicative; a linear ramp would sprint through the informative bottom octaves and crawl the bland top ones. Read the live frequency number at the exact moment a boom or dropout appears, then compare seats: a peak that follows you is a room response, a null that stays fixed to one speaker position is a direct-sound problem worth treating with placement before equalization.

Accuracy, limits and troubleshooting

Small drivers have hard ceilings. Cone area and enclosure volume set what a speaker can move; no browser trick overrides it. If laptop built-ins show nothing below 100 Hz, the test worked.

Re-test loudness-matched. Because of the equal-loudness slope, 60 Hz at equal dBFS sounds much quieter than 1 kHz; when comparing systems, judge by what the speaker is doing (cone motion, absence of buzz), not perceived level.

Turn off DSP that fakes results: TV “loudness” modes, car “Bass Boost”, headphone EQ presets, and spatial-audio renderers all reshape low output, and a 30 Hz “tone” surviving them is usually synthesized, not reproduced.

Port chuffing around 30–50 Hz (a windy noise, not a rattle) means the bass reflex tuning is being overdriven; drop volume two notches and the noise disappears.

Rattles are information. Find the resonating object (shelf, door, driver bezel) before concluding the speaker is faulty; sustained high-level sub-bass on a straining small driver heats voice coils, so keep demo volumes modest and stops quick.

This page reports levels in dBFS relative to digital full scale. It is not a sound pressure level meter; for room SPL in dB use the Decibel Meter with realistic expectations about its calibration limits.

Related tools

• Subwoofer Test — The dedicated hardware diagnostic: 10–120 Hz sweeps, rattle hunt, and crossover checks.
• Low Frequency Hearing Test — Separate your ears’ limits from your speakers’ limits.
• Room Acoustic Test — Map the standing waves this page’s sweep makes audible.
• Sweep Generator — Build custom linear or logarithmic sweeps beyond 250 Hz.

Aliases covered on this page: bass test, bass booster test, sub bass check, bass frequency test, and low end test.