A fan is almost all bass
The ceiling fan recording measures 89% of its power below 250 Hz and a tenth of a percent above 4 kHz. Its spectral centre sits at 130 Hz — lower than every other sound in this preset set except thunder. That is why a fan feels like a presence in a room rather than a sound in your ears.
It also means a fan covers almost nothing bright. Voices, keys, a phone buzzing on wood: all of that sails straight through. If those are your problem, this is the wrong preset and white noise is the right one.
The mistake: buying a fan for masking
People run a real fan all winter for the noise and put up with the cold, which is the wrong trade in both directions. A recording gives you the same 130 Hz body at any temperature, and it does not get louder as the bearings age.
The habit is the point, though, and habits are specific. If your fan is a box fan on the floor rather than a ceiling one, this loop will sound wrong to you. The parent player carries three separate fan recordings; pick the one that matches the room you remember.
Why brown noise sits underneath
A fan recording has a slow cycle in it — the blade passing, the motor loading. At 20%, brown noise smooths the dips in that cycle without adding anything you can pick out. It is the only layer here you should not be able to hear separately.
Turn it off and listen for the wobble. Turn it back on and it goes away. That is the whole job.
The fan loop, measured
Measured on 2026-09-04 from the shipped loop, decoded to 48 kHz mono, loudness from the EBU R128 meter and the spectrum from an averaged 8192-point FFT.
| Layer | Preset level | Loop | Loudness | RMS | Centre | Low / mid / high |
|---|---|---|---|---|---|---|
| Ceiling Fan | 60% | 25.82 s | -16.3 LUFS | -14.1 dBFS | 130 Hz | 89.2% / 10.6% / 0.1% |
| Brown Noise | 20% | generated, no loop | -15.5 LUFS | -13.9 dBFS | 537 Hz | 65.9% / 31.7% / 2.3% |
- Ceiling Fan loop join: the step between the loop’s last sample and its first measures 0.02× that file’s own 99.9th-percentile sample-to-sample move — inside the material, so a butt-join would not tick. The player overlaps each pass by 167 ms regardless.
- What this preset cannot do: A phone speaker cannot reproduce a sound that is 89% below 250 Hz. On a phone this preset will sound thin and cover much less than the numbers suggest; that is the speaker, not the recording.
Play fan noise for sleeping
- Open this page in any browser.
- The preset is already applied: ceiling fan at 60%, brown noise at 20%, timer set to all night.
- Press play through a speaker rather than a phone, so the low end survives.
- Mute the brown noise layer for ten seconds to hear what it is doing, then bring it back.
Frequently asked questions
Is fan noise as good as white noise for sleep?
It is a different shape. A fan puts 89% of its power below 250 Hz; white noise puts 1% there and 83% above 4 kHz. A fan is better for rumble and worse for voices. Choose by what wakes you.
Why does a fan recording sound different from my fan?
Blade count, motor and room all change the sound. This loop is a ceiling fan. The parent player also carries a household fan and a metal table fan, which sit brighter.
Can I use this instead of running a real fan?
For the sound, yes. For airflow, obviously not. The practical gain is being able to keep the noise in winter without keeping the draught.
How long is the loop?
25.82 seconds, the shortest in this preset set. Each pass is overlapped with the next by 167 milliseconds so the join does not tick.
Should the fan run all night?
If it is replacing a fan you used to leave on, yes, and the timer is set that way. A fan that stops at 3am is a change in the room, and change is what causes brief waking.