Press Play for a 50 Hz tone, then step this bass tone generator from 160 Hz down to 20 Hz.
Subwoofer Bass Test: 50 Hz sine tone
Start with your device volume low.
Sine wave · both channels
Hz
Period 20 ms
Wavelength 6.86 m (22.5 ft)
35 cents above G1
Ready. It starts quiet and fades in over half a second.
A steady tone can harm ears and speakers before it sounds loud. Hear nothing? Do not turn it up to find the tone: small speakers cannot play very low tones, and many adults cannot hear very high ones.
Small speakers cannot play this low. Do not turn it up to find it.
This subwoofer bass test is a bass frequency test in ten steady steps. Each row plays one sine tone, and the lowest row that still sounds clean is, by ear, how low your subwoofer goes.
Read the full guide
Run the subwoofer sound test
Press Play: 50 Hz fades in at 10 percent volume. Set a comfortable level once, at half the slider or under, and leave it, so every step is heard at the same setting. Then press the rows from 160 Hz, top of the ladder downward. The four rows from 40 Hz down are the sub bass test, and silence on the last ones is common.
Setup tones for a home theater bass test
Which speakers carry 80 Hz is played with the subwoofer on, then off. Phase control check from the listening seat plays the same tone while you change the subwoofer's phase control.
Do not turn the volume up to find a low row. Step back up the ladder until a tone sounds.
Save WAV writes about 60 seconds of the tone on screen, with the volume slider's level in the file.
Questions and answers
How to test bass output without a meter?
Step down the ladder at one volume setting and note the lowest tone that still sounds clean and steady. That is a check by ear: the page measures nothing, so it gives no decibel figure.
How do I run a car bass test?
Press Save WAV on each tone you want, copy the files to a USB stick or phone and play them in the car, parked with the engine off. For buzzes and rattles, the 40 Hz test tone page has a checklist.
Can I type my own frequency into this subwoofer tone generator?
Yes. The big number takes any value from 20 to 20,000 Hz, to two decimal places, and ÷2 and ×2 under More options move it by an octave. The rows are shortcuts to the standard one-third octave steps.
I hear nothing at 20 or 25 Hz. Is the subwoofer faulty?
Not necessarily. How low a subwoofer plays depends on its cabinet and driver, and small speakers cannot play this low at all. The lowest row that sounded clean is your answer.
Is this a hearing test?
No. It is a test signal for loudspeakers, not a hearing test or a treatment. A tone you cannot hear may be the speaker, the room or the ear, and the page cannot tell which.
All 16 tones
The ladder, 160 Hz down to 20 Hz 10
160 Hz, top of the ladderStart here. Consumer subwoofers cover roughly 20 to 200 Hz, so the subwoofer, the main speakers or both may be playing this tone. The wave is 2.14 m (7.03 ft) long.
125 Hz, where a subwoofer can be placed by earA subwoofer left to play everything under about 120 Hz is handling tones the ear can place. Listen for where this one seems to come from: the front of the room, or the box in the corner.
100 Hz, the live-sound lineConcert subwoofers typically work below 100 Hz. Main speakers that are usable down to 100 Hz can leave everything under this tone to the subwoofer.
80 Hz, between upper bass and mid-bassOne cinema sound certification keeps the subwoofer to tones under 80 Hz. Large dance-music systems call 80 to 100 Hz upper bass and 40 to 80 Hz mid-bass, so this tone sits on their border.
63 Hz, mid-bassThe wave is 5.44 m (17.9 ft) long. Tones this low are hard to place by ear, which is why one subwoofer can stand off to one side and still seem to play from the front.
Show all 16 tones (11 more)
The ladder, 160 Hz down to 20 Hz, continued
50 Hz, the tone this page opens onA sine wave is one frequency with no harmonics. Any buzz, rattle or rasp on top of this hum is added by the speaker or by something in the room, not by the signal.
40 Hz, into the bottom octaveThe line between mid-bass and sub-bass on large dance-music systems. The wave is 8.57 m (28.1 ft) long. From here down the rows show how far this subwoofer reaches.
31.5 Hz, beside the low B of a five-string bassBetween that low B, 30.87 Hz, and the C above it, 32.70 Hz. In a ported box, tones under the port's tuning leave the cone unloaded: it moves a long way and makes little sound.
25 Hz, under the lowest piano noteA piano's lowest A is 27.5 Hz. How low a subwoofer plays depends on its cabinet and its driver, and some have faded by this step. A faint or silent 25 Hz is an answer, not a fault to turn up.
20 Hz, the bottom rungThe lowest tone the tool plays and the low end of the range usually given for human hearing; anything lower is called infrasonic. The wave is 17.1 m (56.3 ft) long. Silence here is common.
Setup checks 4
Which speakers carry 80 HzPlay it with the subwoofer on, then off. If the tone hardly changes, the main speakers are carrying it. If it nearly vanishes, the subwoofer is. Around the hand-over frequency both play together.
Phase control check from the listening seat80 Hz again. A phase control changes when the subwoofer's sound arrives compared with the same tone from the main speakers. Change it while this plays: where both play 80 Hz, the two sounds can cancel more at one setting, and the tone is then weaker.
Wind noise from a ported box25 Hz. An undersized port makes wind noise, or chuffing, when air rushes through it. Listen near the port for a puffing sound riding on the hum. A sealed box has no port and passes by default.
Level check against the main speakers63 Hz. Press this row, then the 125 Hz row, at one volume setting. A subwoofer set far above the main speakers makes the lower tone much the stronger of the two. This is a comparison by ear and measures nothing.
One side at a time 2
Left input alone, 50 HzOnly the left channel carries the tone. With two subwoofers or a stereo pair, the left one alone should sound. A single subwoofer that takes its signal from both channels plays this row and the next.
Right input alone, 50 HzOnly the right channel carries the tone. If the left box plays it, the two inputs are crossed somewhere between the source and the subwoofers.
How this list was compiled: Presets written for this page. Each one is a steady sine tone at a set frequency, on both sides or on one, made in the visitor's browser by this page's own tone generator. The ten ladder frequencies are the nominal one-third octave band centers from 20 Hz to 160 Hz, checked on 2026-10-02 at https://en.wikipedia.org/wiki/Octave_band. Checked the same day at https://en.wikipedia.org/wiki/Subwoofer: a consumer subwoofer typically covers about 20 to 200 Hz, professional live sound uses subwoofers below 100 Hz and one cinema sound certification below 80 Hz; main speakers usable down to 100 Hz can leave everything lower to the subwoofer; large dance-music systems name 80 to 100 Hz upper bass, 40 to 80 Hz mid-bass and 20 to 40 Hz sub-bass; sufficiently low tones are hard to place by ear, a subwoofer left to play everything under about 120 Hz handles tones the ear can place, and port noise also gives its position away; a phase control, which may be a switch or a continuously variable circuit, changes the arrival time of the subwoofer's sound versus those frequencies from the main speakers, and may or may not reduce destructive interference in the range both cover; how low a subwoofer plays depends on its cabinet and driver; enclosures below 20 Hz are called infrasonic. At https://en.wikipedia.org/wiki/Bass_reflex (Limitations): below the tuning frequency the port unloads the cone, which then moves with very large displacements, and an undersized port makes wind noise or chuffing. At https://en.wikipedia.org/wiki/Sine_wave: a sine wave is a single frequency with no harmonics. At https://en.wikipedia.org/wiki/Hearing_range: the range of human hearing is usually put at 20 to 20,000 Hz. At https://en.wikipedia.org/wiki/Standard_tuning: a five-string bass adds a low B below the E of a four-string bass. At https://en.wikipedia.org/wiki/Speed_of_sound: sound travels at about 343 m/s in air at 20 °C. Wikipedia's text is under CC BY-SA 4.0; the facts were checked there and the wording is this site's own. Computed, not looked up: wavelengths (343 m/s divided by the frequency, as the tool itself shows them) and note frequencies in equal temperament with A at 440 Hz (the lowest A of a piano 27.5 Hz, low B 30.87 Hz, the C above it 32.70 Hz). Licence: own work