If you’ve ever been showing a presentation or a video, you know how embarrassing it can be when system sounds such as alerts, errors, and notifications interrupt your audio, especially when you’re projecting to a PA system or loudspeakers.

In OS X, there’s a couple of cool little options that you can apply to your audio settings so that, if you are say, listening to your music while you clean, or showing a movie on your big TV, then you won’t be interrupted by Frog, Funk, Bottle, or any of the other system alerts.

There are three parts to the Sound preferences, “Input”, “Output”, and “Sound Effects”. We want to talk about each one in their own right, starting with the input preferences.

Input Preferences

First open the Sound preferences per your preferred method, usually by clicking open the “System Preferences -> Sound” or using Spotlight and typing “sound”.

With the Sound preferences now open, let’s talk about each tab, starting with the “Input” preferences since they’re the most straightforward.

In our example, we’re using a Macbook Air, which doesn’t come with a ton of input options. But if we’re using a USB microphone or in this case a Bluetooth speaker with a microphone, we can click on each input device and change them as needed.

If we were having a video chat session, we could change the input device on the fly by simple choosing a new one.

For each input device, you can choose the volume level, such as if you have microphones of varying sensitivity or placement.

The internal microphone on many Macs come with “ambient noise reduction,” which automatically cuts down on background chatter and other distractions, but you can turn this off if desired.

Making adjustments to your input devices will probably be unnecessary, but if your coworkers or long distance family members are having a hard time hearing you (or you’re coming through too loudly), then this is how fix it.

Output Preferences

Clicking one tab to the left gives us our “Output” preferences. Note, there’s a persistent “Output volume” slider at the bottom of this preference pane. This is important because it actually applies to each individual output device.

Speaking of those devices, everything that our Mac can possibly output to is listed here, which includes the internal speakers, Bluetooth speakers, HDMI, and AirPlay devices. Just like with our input devices, if you click on another output device, the audio will be played through it.

Each output device has its own balance slider.

Another neat trick is the aforementioned volume slider. Volume levels and mute can be assigned to each output device. In this example, we output to our little Braven BRV-X Bluetooth speaker and the sound is set to medium, but muted.

Clicking over to our Bluetooth receiver, which is connected to larger desktop speakers, we see the volume controls retain their last state for that output device.

Remember this little feature because it will come in handy, not only for protecting your ears and equipment from sudden loud bursts of music, but also with regard to sound effects, which we’ll talk about now.

Sound Effects Preferences

OS X’s “Sound Effects” preferences brings us back to our original scenario, where we want to output sound to one device, but not system alerts and alarms.

The first thing you can do is simply turn off sound effects or turn them down to a point where they won’t bother you.

But you can also route them to a different device. By default they should always play on your computer’s internal speakers or to your Mac desktop’s external speakers, if applicable.

In most situations when you’re outputting audio to an external device, you may not even be able to hear sound effects on the internal speakers however, remember instead of disabling these sounds, you could always just mute your internal speakers.

Bonus Tip: How to Change Your Output Device with a Key and Click

All this wonderful and all, but it really doesn’t make sense to have to keep digging into Sound preferences to change your audio outputs and inputs. Luckily, you don’t have to because of our old friend, the “Option” key.

If you have the menu bar volume control enabled, then when you click it, it will show you the menu slider. It’s kind of useful but we normally use the media keys on our keyboard.

When you hold the “Option” key and click on the volume control, you’re instead shown both your output and input devices. You can also then quickly access the Sound preferences this way too.

Holding the “Option” key makes switching audio devices a snap.

If you’re not keen on the idea of always holding down the “Option” key, there are add-on utility apps, which will place a dedicated menu on the menu bar. In this screenshot, we’ve installed a simple, free app from the App Store called SoundOut.

It doesn’t feature any of our input devices like the “Option” key method, and it’s not specific about what each output is, but if you change devices a lot, and don’t want to hold the “Option” key every single time, then this might be a good solution.

Before we conclude, we should mention that if you attach speakers to your headphone jack, then your output option will change from your internal speakers to headphones.

Headphones and internal speakers are basically the same thing. It’s just something to bear in mind when making changes to audio outputs and sound effects.

Such configurability is fantastic for Mac users who have several different audio devices, because there’s always that time when you connect a Bluetooth speakers and your music begins playing through it at high volume, or you’re showing your favorites home videos and you’re suddenly jarred awake by “Sosumi.”

Thus, you can easily maintain separate audio profiles for each device while eliminating sudden loud interruptions. If you have anything you would like to add, please leave your feedback in our discussion forum.

Profile Photo for Matt Klein Matt Klein
Matt Klein has nearly two decades of technical writing experience. He's covered Windows, Android, macOS, Microsoft Office, and everything in between. He's even written a book, The How-To Geek Guide to Windows 8.
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