How to use the subwoofer test
- Start quiet. Turn your receiver or speakers down first. Low tones sound softer than they are, so don’t keep turning the volume up to hear them.
- Press Play sweep. An up sweep glides from 20 to 200 Hz over 30 seconds.
- Mark what you hear. Press Mark (or M) where the bass first becomes clear, then tag it Lowest bass. Mark and tag anything that rattles, booms or goes quiet.
- Try single tones. On the Tones tab, play the presets from 20 to 200 Hz, or step by 1 Hz with the arrow keys to find the exact rattle.
- Finish with Crossover & phase. Play the phase tone, flip the sub’s phase switch and keep the louder setting.
Copy the result when you’re done. It lists your marks, any room-mode matches and your phase setting.
How the subwoofer test tones work
A subwoofer test plays pure low tones, usually between 20 and 200 Hz, so you can hear how low your system plays and where it rattles or booms. Pure sine tones make problems easy to hear: there’s only one frequency, so a buzz or a dropout stands out.
The sweeps rise or fall on a log scale, the way your ears hear pitch. Each octave takes the same time. The presets follow the standard 1/3-octave steps (20, 25, 31.5, 40, 50, 63 and 80 Hz and so on), so you can compare your results with a speaker’s spec sheet.
Like any hz tester in a browser, this subwoofer frequency test can’t measure loudness in decibels. For levels, use your receiver’s automatic calibration or a sound level meter app. Below 20 Hz the tool asks first and plays at half the level, because most subwoofers can’t play that low.
Understanding your results
| What you notice | What it usually means | What to do |
|---|---|---|
| Bass becomes clear at 25–40 Hz | Normal roll-off for a home subwoofer | Compare with your model’s rated low-frequency limit |
| A rattle at one frequency | A loose object, panel or screw | Tighten, pad or move it, then replay that tone |
| One very loud note | A room mode (a peak) | Enter your room size and move the sub |
| One note almost disappears | A room mode (a dip) or a phase problem | Move the sub or your seat, then run the phase check |
| A hole near the crossover | Wrong phase or crossover setting | Run the crossover sweep and the phase tone |
| Silent everywhere | No power or no signal | Check the power switch, the cable and the receiver’s subwoofer setting |
Phone and laptop speakers play little below 100 to 200 Hz. If those stay silent in this bass test, that’s expected.
How to fix a weak, boomy or rattling subwoofer
Placement changes bass more than any setting. Try the subwoofer crawl: put the sub at your listening seat and play the Slow sweep. Then crawl around the room at floor level and listen. Where the bass sounds most even, put the subwoofer there.
Next, set the crossover. 80 Hz is a common starting point for home theater, but check your receiver’s manual. The crossover sweep should hand over smoothly from the sub to the speakers, with no hole or bump.
Then set the level, ideally with your receiver’s calibration or a sound level meter app. A sub that’s too loud sounds boomy; one that’s too quiet sounds thin. To see room peaks instead of only hearing them, play the slow sweep and watch the peak hold trace in the spectrum analyzer on a second device.
Subwoofer phase check
Play the phase tone at your crossover frequency and flip the sub’s phase switch between 0° and 180°. Keep the setting where the tone sounds loudest at your seat. If both sound the same, phase matters little in your room, so focus on placement.
Rattles and buzzes
Use the Tones tab to find the exact frequency, then hold it while you touch shelves, frames and panels. Tighten loose screws, add felt pads, and move objects off the subwoofer.
Bass test for headphones, earbuds and car audio
Headphones and earbuds
Run the up sweep at a comfortable volume. Good over-ear headphones often play down to about 20 Hz. For earbuds, play a 50 Hz tone and press them in gently. If the bass jumps, the seal is poor: try bigger ear tips. To check left and right, the full range and 3D sound in one run, use the headphone test.
Car subwoofer test
Connect your phone by Bluetooth or AUX, park with the engine off, and start quiet. The slow sweep finds rattling door panels and trunk lids. Check the amplifier’s gain and low-pass filter settings before you add level. Pulses at 40 or 50 Hz are a quick deep bass test for punch.
Phone and laptop speakers
Small speakers can’t move enough air for deep bass. A subwoofer bass test will often stay silent on them below 100 to 200 Hz, which doesn’t mean they’re broken.
For tones above 200 Hz, use the tone generator. To check the subwoofer channel of a home theater, run the 5.1 surround sound test, and check your main speakers’ phase with the left right sound test.