How to run the subwoofer test
- Turn the volume down, then press 60 Hz. Raise the volume slowly until you clearly hear or feel the bass.
- Step down through the subwoofer test tones – 50, 40, 35, 30, 25, 20 Hz. Note the last one that still sounds clean and strong.
- Run the bass sweep. The tone falls smoothly from 120 Hz to 15 Hz in 40 seconds. Press the button when the bass disappears to see roughly where your system stops.
- Listen for buzzing or rattling during the sweep. The frequency on screen tells you which tone sets it off.
Have more than one sub? Run the bass test subwoofer by subwoofer, unplugging the others, so you know each one works on its own.
What you should hear at each frequency
| Bass test Hz | What to expect |
|---|---|
| 20–25 Hz | More pressure than sound. Only large or high-end subwoofers play it cleanly. |
| 30–35 Hz | Deep rumble, like distant thunder. A good home subwoofer handles it. |
| 40–50 Hz | Solid, punchy bass. Almost every subwoofer should play this well. |
| 60 Hz | Easy to hear. Bookshelf speakers start to join in here. |
| 80 Hz | The usual crossover point between subwoofer and main speakers. |
| 100–120 Hz | Upper bass. You can start to hear where the sound comes from. |
The 20 Hz bass test is the hardest one. If your system plays 30 Hz cleanly but not 20 Hz, that's normal for most home and car setups. Phone, laptop and TV speakers rarely go below 100–200 Hz, so use a real subwoofer or good headphones for a meaningful subwoofer bass test.
Subwoofer not working? Check these
- Power and standby: many subs have an "auto" mode that sleeps after silence. Play 50 Hz for a few seconds and watch the power light.
- The cable: a home theater sub normally connects to the receiver's "Sub" or "LFE" output with an RCA cable. Try another cable if nothing comes through.
- Receiver settings: the speaker setup must say Subwoofer: Yes, and the main speakers are often set to "Small" so their bass goes to the sub.
- Crossover and volume knobs: on the sub itself, turn the volume to the middle. If your receiver handles the crossover, set the sub's own crossover knob to its highest value or to "LFE/bypass".
- Car audio: check the amplifier's fuse and remote-on wire, the gain setting and whether its low-pass filter is switched on.
Set the phase with the 80 Hz tone
Sit in your usual seat and play 80 Hz so it comes from both the sub and the main speakers. Ask someone to flip the sub's phase switch between 0° and 180° (or turn the phase knob slowly). Keep the setting where the bass sounds loudest: that's where the subwoofer and the speakers add up instead of cancelling each other.
Find the best spot in the room
Bass depends heavily on the room. Reflections from walls add up in some spots and cancel in others, so the same sub can sound huge in one seat and thin in the next. Try the "subwoofer crawl": put the sub at your listening position, play a 40–50 Hz tone (or turn on Pulsed), and move around the floor where the sub could go. Where the bass sounds strongest and cleanest, place the subwoofer.
To check the rest of your system, use the left right audio test for channels and the headphone test for headphones. For a tone at any other frequency, try the tone generator.
How we tested this tool
We recorded the tool's output in a browser and measured it: every bass test tone came out at its labelled frequency, the sweep frequency shown on screen matched the tone being played, the pulsed mode switched the sound on and off every half second, and the volume slider changed the level as expected. We haven't measured it on real subwoofers yet; tell us through the contact page how your system did.
Frequently asked questions
Why can't I hear the 20 Hz bass test tone?
20 Hz is at the very bottom of human hearing and is felt more than heard. Many subwoofers roll off below 25 to 35 Hz, and phone, laptop and TV speakers can't play it at all. If 30 Hz works but 20 Hz doesn't, your setup is normal.
Can a bass test damage my subwoofer or speakers?
Yes, if it is played too loud. Very low tones make speaker cones move a long way. Start with the volume low and stop immediately if you hear clicking, slapping, buzzing or distortion. Small speakers are most at risk.
Why is the bass loud in one spot and weak in another?
Room reflections add up in some places and cancel in others, creating peaks and dips at certain bass frequencies. Moving the subwoofer or the listening position changes them; play a 40 or 50 Hz tone and walk around to hear it.
Should the subwoofer phase be 0 or 180 degrees?
Whichever sounds louder at your listening seat with the 80 Hz tone playing through both the main speakers and the subwoofer. More bass at the crossover means the sub and speakers are working together instead of cancelling.
Does this subwoofer test work in a car?
Yes. Connect your phone by cable or Bluetooth, start with low volume and use the bass sweep to find the frequency where panels or the trunk lid rattle, then dampen or tighten that part.