A constant whooshing hum under your voice is one of the most common stream audio problems, and it usually traces back to your own PC’s fans sitting inches from an open microphone. The fix is a layered approach: reduce the noise at the source, position your mic smartly, and clean up the rest in software, in that order.
Why fans end up in your audio
Sensitive microphones, especially condensers with wide pickup patterns, capture the broadband hum of case, GPU, and CPU fans running under load while you game and stream. The closer and louder the PC, and the more sensitive and distant the mic, the worse it gets. Because it is a steady sound present while you talk, it is harder to remove than intermittent noise.
Source, position, software
Effective fixes attack the problem in three layers. Reducing the actual fan noise is the most powerful; smart mic choice and placement is next; software suppression is the final polish. Skipping the first two and leaning entirely on noise suppression leaves you with artifacts and a watery voice.
Fixes ranked
| Fix | Layer | Impact |
|---|---|---|
| Move PC farther / on floor | Source | High |
| Better fan curves / quieter fans | Source | High |
| Dynamic mic, close-miked | Position | High |
| Cardioid pattern aimed away from PC | Position | Medium |
| Noise suppression filter | Software | Medium |
Reduce the noise at the source
Move the PC off the desk and onto the floor, ideally on the far side from your mic, so distance and the desk itself dampen the sound. Set smarter fan curves in your motherboard software or a fan utility so fans do not spin to maximum unnecessarily; keeping components cool with good airflow lets fans run slower and quieter. Cleaning dust and replacing screaming stock fans with quieter models also helps a lot.
Choose and place the mic wisely
A dynamic microphone used close (a few inches from your mouth) rejects distant room noise far better than a sensitive condenser placed a foot away. Aim the mic’s cardioid pattern so its rear, the least sensitive side, points toward the PC. Close-miking lets you lower the gain, which shrinks how much background hum the mic captures relative to your voice.
Finish in software
After the physical fixes, add a noise suppression filter in OBS (RNNoise is a good free option) and a gentle high-pass filter to trim low rumble. Because fan noise is steady, suppression works better once you have already minimized it, apply just enough to clean the residue without making your voice sound processed.
Balancing cooling against silence
Quieting fans must not cook your components. The goal is a smart fan curve, not disabling cooling. Set fans to ramp gradually so they stay quiet at idle and low load, only spinning up when temperatures genuinely climb. Larger fans moving air slowly are quieter than small fans spinning fast for the same airflow, so case and cooler choice matters. Good airflow lets everything run cooler and therefore quieter.
GPU noise under streaming load
The GPU is often the loudest component while gaming and encoding. A modest undervolt can cut heat and fan speed significantly with little performance loss, and a custom GPU fan curve prevents the sudden whoosh that a sensitive mic loves to capture. Keeping the case and GPU dust-free also keeps fan speeds, and noise, down.
Isolation as a last resort
If the PC simply must sit close and loud, physical isolation helps: place it in a well-ventilated cabinet or on the floor behind a barrier so the desk and distance absorb noise. Never seal a PC in an airtight space, but a partial acoustic break between the tower and your microphone reduces what the capsule picks up.
FAQ
Will noise suppression alone fix fan noise?
Partially, but heavy suppression degrades your voice. Reduce the noise physically first, then use suppression lightly for the remainder.
Is a dynamic mic really better for a loud PC?
Yes. Used close, a dynamic mic rejects distant fan noise much better than a condenser, making it the go-to for loud rooms and untreated spaces.
Will noise suppression alone remove fan noise?
Only partially, and heavy suppression makes your voice sound watery and processed. Because fan noise is a steady sound present while you talk, the better approach is to reduce it physically first: move and quiet the PC, use a close-miked dynamic microphone aimed away from the tower, then apply light suppression for the residue. Physical fixes first make the software cleanup gentle and natural rather than destructive.
Bottom line
Stop fan noise in layers: move and quiet the PC, use a close-miked dynamic microphone aimed away from it, then apply light noise suppression and a high-pass filter. Physical fixes first make the software cleanup effortless.
