You're wearing headphones, listening to music at a comfortable 40% volume. A Slack notification fires. DING. It's deafeningly loud compared to your music. Your ears ring. You rip off your headphones.
This happens because macOS doesn't let you separately control the volume of notifications versus media. Your music might be at a comfortable level, but alert sounds — Slack pings, Mail notifications, Calendar reminders, macOS system sounds — blast at full intensity relative to your system volume.
Why notifications sound louder than music
Notification sounds are short, sharp audio bursts designed to get your attention. They have high peak volume by design. Music, by contrast, has a wide dynamic range — quieter passages, louder passages, and an overall mastered level that's meant for sustained listening.
When your system volume is at 40%, your music sits at 40% of its mastered level — which might be a comfortable 60-70 dB in your headphones. But a notification ding at 40% system volume might still hit 80+ dB because the notification sound file itself is mastered at a much higher peak level. The system volume scales both equally by percentage, but their starting levels are very different.
In headphones, this is worse. The sound is going directly into your ear canal with no room to dissipate, so the perceived volume difference between quiet music and a sharp notification ping is amplified.
Built-in ways to reduce notification volume
Lower the alert volume
macOS has a separate "Alert volume" slider buried in settings. Go to System Settings → Sound and look for the Alert volume slider. This controls the volume of system sounds and alerts separately from the main volume.
Limitation: This only affects macOS system alerts (like error beeps and Trash sounds). It doesn't affect notification sounds from apps like Slack, Discord, or Teams, which play their own audio through their own audio engine.
Disable notification sounds per app
Go to System Settings → Notifications, select the app that's too loud, and toggle off "Play sound for notifications." This silences that app's notifications entirely.
Limitation: It's all-or-nothing. You can't make Slack notifications quieter — only fully on or fully off. And you lose the audio cue that tells you something happened without looking at your screen.
Use Focus modes
Focus modes (Do Not Disturb, Work, etc.) can suppress notification sounds from all or selected apps. This works during deep focus sessions but isn't practical all day — you'd miss important notifications.
The real fix: control notification app volume independently
What you actually want is simple: make Slack quieter without making your music quieter. Lower notification app volumes to 15% while keeping Spotify at 50%. macOS doesn't let you do this.
SoundDial does. It gives every app its own volume slider, so you can set notification-heavy apps like Slack, Mail, and Calendar to a much lower volume while keeping your media apps at a comfortable level.
A typical headphone-friendly setup
- Spotify / Music — 50% (comfortable listening level)
- Slack — 15% (noticeable but not startling)
- Mail — 10% (subtle ping, won't jolt you)
- Calendar — 20% (enough to notice, not painful)
- Zoom / FaceTime — 90% (clear call audio)
- Browser — 40% (matching music level for video playback)
Save this as a "Headphones" profile in SoundDial and apply it with one click whenever you plug in. Create a separate "Speakers" profile with different ratios for when you're working at your desk.
Get SoundDial on the Mac App Store — €14.99 one-time purchase, no subscription, macOS 14.2+.