Free desktop app for game masters
Keep the sound flowing. Change scenes in one click.
Music and ambience blend between scenes without audible cuts. Find sounds, adjust the mix and trigger effects from one window.
Apple silicon (M1 or later) · macOS 13 or newer
Windows 10 or 11 · 64-bit
Gapless loops and crossfades
Every sound loops without a gap and scenes blend. Nothing cuts out.
Scene changes in one click
Sounds both scenes share keep playing. Click as fast as you like.
A soundboard that sounds alive
Presses overlap and vary in pitch, so sword hits never sound the same.
Real-time acoustics
The echo of a room, hall, cathedral, cave or underwater.
Deep library tools
Tags, roles, folders, playlists and a search that forgives typos.
Your files stay yours
Never moved or changed. It saves itself, with automatic backups.
Light and dependable
Long tracks stream from disk. Tested for 6 hours non-stop.
Free and offline
No account, no internet. For Mac and Windows.
Your players decide. The sound follows.
A soundscape saves your music, ambience and volume levels together.
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Layer the atmosphere
Mix music with background sounds and save it as a soundscape.
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Change scenes in one click
Shared sounds keep playing. The rest fade in or out.
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Add effects on cue
Play a sword clash or a creaking door over the mix.
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Sound like a place
Add a room, cave or cathedral echo to ambience and effects.
Find the sound you need.
Bring your own music, ambience and effects. Label and tag sounds, then find them by search, filters or folder.
Label and tag · Search and filter · Browse folders
Your audio files stay in their original folders.
Questions
What exactly is it?
GM Audio Mixer is a free desktop app for Mac and Windows that plays and manages the background audio for your game: music, ambience and sound effects. It’s made for tabletop roleplaying games, and works just as well for board games or any other game night. It runs offline, on your own computer.
Is it really free?
Yes. GM Audio Mixer is free, with no trial or in-app purchases. No account is required.
Can I play Spotify or YouTube?
GM Audio Mixer plays audio files stored on your computer. It does not play Spotify, YouTube or other streaming services.
Which computers does it run on?
Macs with Apple silicon (M1 or later) running macOS 13 or newer, and 64-bit PCs running Windows 10 or 11. Intel Macs are not supported.
Can I use it on Discord?
Yes, with additional audio-routing software. The app’s Help explains how to send its audio to Discord.
Is it only for D&D?
You can use it for any tabletop RPG, as well as board games. Choose sounds that fit your game and setting.
How do I install it?
Follow the install steps for your operating system, including any confirmation shown the first time you open the app.
Why did you build this?
I built it for my own D&D sessions. I love using sound to make a session more immersive, but my old setup with a bunch of Winamp windows didn’t cut it anymore, so I built something better. It turned out pretty sweet, so I wanted to share it with everyone.
Try it at your next game night.
Download GM Audio Mixer and build the sound of your next session.
Apple silicon (M1 or later) · macOS 13 or newer
Windows 10 or 11 · 64-bit
If you’d like to support the project,
Toss a coin to your GMInstall GM Audio Mixer
There’s no installer: on a Mac you drag the app to Applications, on Windows you unzip one folder. The first time, your computer asks you to confirm, because the app isn’t notarized by Apple or code-signed for Windows.
Install on a Mac
- Open the .dmg and drag GM Audio Mixer to Applications.
- Open it. In the warning, click Done, not Move to Trash.
- Open System Settings › Privacy & Security and click Open Anyway.
More help with installing
Open Anyway is under Security, near the bottom. Enter your password, then click Open. It stays there for about an hour after step 2; if it’s gone, do step 2 again.
You do this once for each new version, because the app isn’t notarized by Apple. Control-click › Open no longer works since macOS 15.
Still won’t open? Open Terminal, paste this line and press Return, then open GM Audio Mixer again:
xattr -dr com.apple.quarantine "/Applications/GM Audio Mixer.app"Install on Windows
- Right-click the zip, choose Properties, tick Unblock and click OK.
- Extract it to a folder of your own, not OneDrive or Program Files.
- Run GM Audio Mixer.exe. If Windows warns you, click More info, then Run anyway.
More help with installing
To extract, right-click the zip and choose Extract All…, for example into C:\Users\<you>\RPG.
The warning in step 3 is Microsoft SmartScreen. It shows up for apps it doesn’t know yet, and it can come back with each new version.
If Smart App Control blocks the app, it can only run with Smart App Control switched off (Windows Security › App & browser control › Smart App Control settings).
Keep your own sound library outside the GM Audio Mixer folder, because updates replace that folder.
Updating later? A new version is a new download, installed the same way, and your library is never touched. On Windows, delete the old GM Audio Mixer folder first and extract the new one in its place. Both downloads include a READ ME FIRST file with these steps.
Credits
The demo library sounds as good as it does because people share their work online. Thank you all!
Music by Ian Fisher of Tabletop RPG Music
Ian kindly let me include eight of his tracks in the demo. I’m a big fan of his music, and I think you’ll hear why. If you like what you hear, find more on Tabletop RPG Music and support him on Patreon.
Music used with permission.
Ambience
Sounds shared on ambient-mixer.com by acclivity, Benboncan, braffe2, Corsica S, Crpdeth, Digifish Music, Felix Blume, Flame, George Vlad, GoodListener, ingeos, juskiddink, KaiLietzke, kangaroo, klangmanufaktur, klankbeeld, kvgarlic, leosalom, lonemonk, Mariusz Jasionowicz (RareSound), Mikes-MultiMedia, Monterey2000, Noise Collector, Reinsamba, rikkisch, Ronfont, ryancacophony, Ryding, salty sam, SoundLikeTube, stackpool, Tomlija, toddbradley, urupin, Vinicius, waterboy920, willstepp, Zabuhailo and many others.
Sound effects
Sounds shared on pixabay.com by AlesiaDavina, CreatorsHome, DavidDumaisAudio, DRAGON-STUDIO, LordSonny, PhatPhrogStudio, Universfield, Yodguard and others, and on freesound.org by Reitanna.
Icons
The app’s sound icons, and the coins and the other game icons on this page, come from game-icons.net, made by Andy Meneely, Carl Olsen, Caro Asercion, Cathelineau, Catsu, DarkZaitzev, Delapouite, Faithtoken, GeneralAce135, Guard13007, HeavenlyDog, John Colburn, John Redman, Kier Heyl, Lorc, Lord Berandas, Pepijn Poolman, Pierre Leducq, Quoting, Sbed, Seregacthtuf, Skoll, Sparker, Starseeker, Willdabeast, Zajkonur and various other artists. CC BY 3.0, recolored, background removed.
Fonts
Young Serif, Atkinson Hyperlegible Next and JetBrains Mono, under the SIL Open Font License 1.1.
Every sound is listed with its source and license in Credits.txt inside the demo library, and in About & credits in the app.
D&D is a trademark of Wizards of the Coast. Spotify, YouTube, Discord and Winamp are trademarks of their owners. GM Audio Mixer is not affiliated with or endorsed by any of them.