Low-frequency test tones for subwoofers and bass
Find out how low your subwoofer really goes, locate room modes that wreck your bass, and track down rattles - using clean 20-200 Hz tones.
Open the bass testBass is the hardest part of any system to get right, and it's rarely the subwoofer's fault. Long wavelengths interact with your walls, creating spots where notes boom and spots where they vanish. A clean low-frequency tone is the only honest way to hear what's happening, because music almost never holds a single bass note long enough to judge.
TestTones plays pure sine tones down to 20 Hz straight from your browser. The speaker test section has one-tap bass buttons for 20, 30, 40, 50, 60, and 80 Hz, and the main generator and sweep let you cover the full 20 to 200 Hz region with 0.1 Hz precision.
Step down from 80 Hz toward 20 Hz and hear exactly where your sub stops producing usable output.
A slow low sweep exposes the boomy peaks and dead nulls your room adds to every bass note.
Hold one tone and walk the room to find the shelf, vent, or window that buzzes back.
Open the speaker test and find the subwoofer / bass test card. Start at 80 Hz - almost any sub handles that - and confirm you hear a clean, steady tone. Then step down: 60, 50, 40, 30, and finally 20 Hz. Keep the volume constant. At some point the tone gets much quieter or turns into a soft flapping sound rather than a clear pitch. That's your sub's practical limit.
One caution: below about 30 Hz you may feel the tone more than hear it, and pushing the volume to "make it louder" forces the cone into huge excursions. If you hear a chuffing or distressed sound, back off - you're past what the driver or port can do cleanly, not gaining real bass.
Room modes are the single biggest reason bass sounds uneven from seat to seat. They happen at frequencies tied to your room's dimensions, and they're easy to find by ear.
In the sweep section, set the start to 20 Hz, the end to 200 Hz, choose logarithmic, and use a long duration like 30 to 60 seconds so the tone moves slowly. Sit in your normal listening spot and listen for notes that jump out far louder than the rest (peaks) and notes that nearly disappear (nulls). Those are your room modes.
To confirm a specific problem frequency, switch to the main generator, dial it in, and move your head or walk around. If a 45 Hz note is thunderous on the couch but gone two feet away, that's a standing wave. The fix is placement - moving the sub or the seat often helps more than any equalizer.
Probably not. Two things are at play: human hearing is far less sensitive at 20 Hz (you need much more level for it to seem as loud as a 60 Hz tone), and many subs roll off before 20 Hz. If 30 and 40 Hz are strong and clean, your sub is fine - it just doesn't reach the very bottom.
Sustained very low frequencies at high volume can over-extend a driver, especially ported designs below their tuning frequency. Keep the level moderate, listen for any chuffing or distress, and don't hold a 20 Hz tone at full blast.
Not meaningfully. Soundbars and laptops can't reproduce deep bass at all, so the test just confirms their limits. Use a real subwoofer or full-range speakers for results that mean anything.
Pink noise (in the speaker test) is great for a quick overall balance check, but single tones are better for pinpointing a specific room mode or rattle because you know exactly which frequency you're hearing.
Useful additions for measuring and dialing in low-frequency performance:
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Open the free bass test, sweep, and generator - all in your browser, down to 20 Hz.
Start the bass testChannel balance, polarity, and sweeps
Check your high-frequency limit at home
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