Microphone Beta

nomus can sit between your microphone and your call app. It turns down keyboard clatter, fans, music and other people talking in the background, and keeps the voice at the mic. It runs on your computer: nothing you say is recorded or sent anywhere.

An early-access beta. In our tests the microphone cleaner is clearly cleaner than no filter at all, but it is not yet as clean as the best noise-cancelling tools. From 0.11.2 the macOS and Linux apps useHigh quality by default. Their Standard setting uses a newer model, mic4b, which removed about 1.5 dB more noise and music than mic2 (the model in Chrome and in the 0.10 apps) on our test sets; it has not yet been measured on real Mac recordings. A quieter voice is the trade we chose over letting noise through, and your own singing may be turned down too. Tell us what you hear: support.

On a Mac

You need the nomus app 0.10.0 or newer (macOS 14.2 or newer) and the small nomus Microphone driver. To install or update the app, paste curl -fsSL https://agrohi.com/nomus/install | sh in Terminal, or use the download page. That line installs only the app; the driver comes next, from the app. The driver adds a microphone called nomus Microphone to macOS; the app writes your cleaned voice into it.

Install the driver from the app (easiest)

Open nomus and turn on Microphone. From version 0.10.1, nomus explains that it needs the driver and installs it for you; in 0.10.0, press Install driver on the Microphone card.
macOS asks for your administrator password once. Sound stops for about two seconds while macOS reloads its audio system.
Microphone turns on. Allow microphone access when macOS asks.
In your call app, open its audio settings and choose nomus Microphone as the microphone. Pick your real microphone in nomus if the default is not the one you want.

Apps without a microphone menu Experimental

Some apps, such as WhatsApp for Mac, always use the Mac's default input. For them, nomus 0.10.1 has an experimental switch on the Microphone card, off unless you turn it on: Use nomus Microphone as my default input while on. nomus remembers your current input, makes nomus Microphone the default while Microphone is on, and puts your input back when Microphone turns off or nomus quits. If you pick another input yourself, nomus leaves your choice alone. It has not yet been tried on many Macs.

If your input ever stays on nomus Microphone, pick your mic in System Settings > Sound > Input.

Or install it in Terminal

The same driver as a separate download, if you prefer to see each step. Paste this in Terminal. It downloads the zip, checks its checksum, unpacks it and runs the installer, which asks for your password:

cd ~/Downloads &&
curl -fLO https://agrohi.com/nomus/download/nomus-driver_0.10.0.zip &&
echo "4ee76f9452717327b1364cb9326f1f7af3142454204cdb502d471d62b2e84495  nomus-driver_0.10.0.zip" | shasum -a 256 -c &&
rm -rf nomus-driver && ditto -x -k nomus-driver_0.10.0.zip . &&
xattr -dr com.apple.quarantine nomus-driver &&
sudo nomus-driver/install.sh

nomus-driver_0.10.0.zip, sha256 4ee76f9452717327b1364cb9326f1f7af3142454204cdb502d471d62b2e84495. The installer checks the bundle's identity, its file hashes and its code signature, copies onlynomus.driver into /Library/Audio/Plug-Ins/HAL, and restarts Core Audio. The driver is signed ad hoc and not yet notarized by Apple, which is why the block clears the download flag itself.

Remove it

Press Uninstall driver on the Microphone card, or run sudo ~/Downloads/nomus-driver/uninstall.sh. Either removes only nomus.driver.

On Linux

Install the nomus app 0.10.0 or newer: on Debian or Ubuntu, pastecurl -fsSL https://agrohi.com/nomus/install | sh in a terminal, or use thedownload page. It needs PipeWire 0.3.49 or newer; there is no driver to install.
Turn on Microphone in nomus.
In your call app, choose nomus Microphone as the microphone. nomus changes none of your default devices, and nomus Microphone is gone when you turn it off or quit.

"Hear yourself" is Mac-only in this beta.

In Chrome

Update the nomus extension to 0.5.0, open its popup and tickClean my mic. Version 0.5.0 is not yet in the Chrome Web Store (coming soon); meanwhile the desktop app covers Zoom, FaceTime, Teams and other apps: use nomus Microphone from the Mac or Linux app.
Chrome asks to allow nomus on Google Meet, the Zoom web client and Discord. Allow it. Untick the box and nomus gives that access back.
Join or rejoin a call. Pick your microphone as usual; nomus cleans it before the site hears it.

How much delay it adds

The filter itself, High quality (default, Mac and Linux): 40 ms
The filter itself, Standard (Mac and Linux option; Chrome): 20 ms
Mic to call app, Mac: ~55-60 ms High quality, ~35-40 ms Standard
Mic to call app, Linux: ~61 ms High quality, ~52 ms Standard
CPU: ~3% High quality, under 2% Standard

Measured on our machines: the Mac figures through nomus Microphone, the Linux figures through PipeWire at a 512-frame cycle (a 1024-frame cycle roughly doubles them). The Mac High quality figure is the Standard one plus the 20 ms the filter adds, not yet measured end to end on a real Mac; the Linux figures come from our test container. CPU is for one core of a recent laptop. Bluetooth headsets add their own delay on top.

High quality or Standard Beta

The macOS and Linux apps have a Quality setting on the Microphone card. From 0.11.2,High quality is the default: it uses DeepFilterNet3, an open-source noise suppressor that ships inside the app. On our first six real Mac recordings it kept the voice closer to the original and sounded cleaner with music and typing around it than Standard. It waits 20 ms longer before it lets your voice through, so calls get 20 ms more delay, and it uses about 3% of one processor core instead of under 2%. Standardis our own model (mic4b): the lowest delay, lighter on CPU. Choose it any time; the app keeps your choice. If you used 0.11.0 or 0.11.1, the app moves you to High quality once and says so on the card. You can switch during a call: the sound pauses for a moment and comes back. If the High quality model file is missing or damaged, the app keeps Standard and says why. The Chrome extension uses Standard (DeepFilterNet3 cannot run in the browser yet); Android has no microphone cleaner.

What it does not do

Phones: There is no microphone cleaner for Android or iPhone. iOS does not let an app process another app's audio, and the Android app only filters sound that other apps play.
Microsoft Teams in a browser: Not supported. Teams' pages forbid the WebAssembly our engine runs on, so Clean my mic cannot run there. On a Mac or Linux PC, any app that lets you pick a microphone can be given nomus Microphone; we have not yet tested Teams itself.
Calls that ask for camera and microphone together: Chrome's Clean my mic leaves such a request untouched, and Google Meet and the Zoom web client often ask that way. Use nomus Microphone from the Mac or Linux app instead.
Echo: nomus does not remove echo from your speakers. Wear headphones, or leave your call app's echo cancellation on.
Loud rooms and close voices: Loud music, or several people talking close to you, can still come through. Your own singing may be turned down, because the cleaner is built for speech.
Sites that ask for original sound: If a call app turns off its own noise suppression for a music mode, nomus leaves that microphone alone.
Windows: No microphone app. Windows would need a signed audio driver.
nomus Microphone is not in my call app's list: Turn the Microphone switch on in nomus first, then reopen the call app's audio settings. On a Mac, check that the driver is installed (the Microphone card says so). On Linux, check that your system runs PipeWire.
"Driver installed but not loaded", or "macOS audio did not restart": The driver is on your Mac, but macOS has not loaded it yet. Press Restart audio on the Microphone card (nomus 0.10.2 or newer): macOS asks for your password once and sound stops for about two seconds. If nomus Microphone still does not appear, run sudo killall coreaudiod in Terminal, or restart your Mac. nomus 0.10.0 and 0.10.1 could say "Driver not installed" here by mistake: on macOS 14.4 and newer their way of restarting audio is refused, so the driver stayed unloaded until a restart. Update to 0.10.2.

Privacy: the microphone is processed on your device and never recorded or sent anywhere. Read the details.