Audio Effects

SoundSource makes it easy to apply audio effects to any audio playing on your Mac. This page provides details on effects you can use with SoundSource.

Built-In Effects

SoundSource includes four powerful audio effects to help you improve the sound of your audio. We've worked to make these built-in effects simple to use, so anyone can get great-sounding audio.

Magic Boost

When you activate Magic Boost, you'll get richer, fuller sound from any source. Magic Boost listens for quiet passages of audio, and gives them a healthy boost, while leaving louder audio untouched. Whatever your audio source, Magic Boost will give you tremendous volume, all with a single click. It's perfect for maxing out small speakers like those found on Mac laptops.

Volume Overdrive

While Magic Boost will increase the level of quiet portions of audio, Volume Overdrive can assist in getting extra volume out of your speakers. It will amplify audio from individual applications up to 400%, making it possible to hear your audio even in loud environments.

Volume Overdrive uses limiting to improve the quality of overdriven audio, by preventing digital distortion. This works very well to amplify quiet audio, without blowing out sound that's already loud. This does mean that when you're listening to louder audio, you may not notice much boost when using Volume Overdrive.

Note that Volume Overdrive is not available on the system's default output. It must be applied to individual apps, within SoundSource's Applications section.

Comparing Magic Boost and Volume Overdrive

Magic Boost and Volume Overdrive can both increase the volume of audio, but they do so in different ways.

Magic Boost works to keep all audio at the same level, by raising the volume of quiet portions while leaving louder parts unaffected. This complex adjustment is often useful, but flattening the difference in levels can occasionally produce audio which sounds strange to the ear.

Volume Overdrive allows you to boost volume levels past 100%, maxing out the volume while maintaining the relative difference between quiet and loud portions. This is a simpler adjustment which attempts to get more out of your speakers for all audio.

10-Band Lagutin Equalizer

For almost two decades, Rogue Amoeba's renowned 10-band Lagutin equalizer has helped users get better sound.

From the EQ's inline view, you can select from almost two dozen presets to adjustment any time you play audio.

For more control, click to reveal the full popover. From here, you can configure the EQ manually.

Once you've set it, you can even save your own custom equalizer settings. Adjust the equalizer to your liking, then select Save Preset As… from the Presets menu.

Headphone Equalizer

Headphone EQ provides automatic calibrated equalization for headphones, powered by the well-known AutoEq project. Use it when playing audio to headphones to make them sound their very best.

Headphone Equalizer is available exclusively on the default output device. Add the effect, then browse by name for the profile for your specific headphones.

Profiles are available for thousands of different headphone models. Select the appropriate model to apply audio adjustment tuned precisely to get the best out of your exact headphones.

Using custom-created EQ Profiles

With SoundSource 5.3 and higher, it's possible to manually load custom EQ profiles into Headphone EQ. For full details, see this article.

Audio Unit Effects

SoundSource also features support for Audio Unit effects. These advanced audio effects provide complex audio adjustments. Using Audio Unit effects, you can adjust audio in countless ways to get the exact sound you want, from any application, or from your entire system.

SoundSource offers access to over a dozen Audio Units provided by Apple as part of MacOS. It also works with third-party Audio Units you've installed yourself. It will find Audio Units in two locations:


When a compatible Audio Unit is installed in either of these locations, SoundSource will include it in the menu shown when clicking Add Effect for either the System Output device, or a per-application adjustment.

Audio Unit Search

SoundSource sorts Audio Units by their developer, using sub-menus to make it easier to locate the desired effect. If you have a large number of Audio Units, however, the Audio Unit Search should prove helpful.

The search field is available within the Add Effect menu. Type a few characters of the name of your desired effect into this search field, and it should appear in the list for easy selection.

Generic Interfaces for Audio Unit Effects

Many Audio Unit effects have custom interfaces, which can occasionally cause issues or crashes. SoundSource can optionally use these effects with a generic interface instead, providing access to all controls. This can be helpful in avoiding issues, as well as making effects simpler to work with for VoiceOver users.

To toggle between the generic and custom interfaces, control-click on an effect and select Use Generic Audio Unit Interface or Use Custom Audio Unit Interface. To load the generic interface by default, hold the Shift key when adding the effect.

Audio Effects Indicator

To see which of your audio sources are being adjusted through the use of audio effects, look for the helpful FX indicator on the Hide/Show Effects button:

In the example screenshot below, audio effects are being applied to the System Output device, and to Spotify's audio, while audio from Safari and Chrome is not being adjusted.

Effect Nicknames

In each audio effect’s popover, you’ll see the effect’s default name. Next to that name is an Edit pencil. When you click this, you’ll be able to modify the name of the effect.

In the image above, two identical effects have each been given nicknames, to help distinguish them from one another. Effect nicknames are very useful for keeping track of what each effect is doing in your sessions.

Bypassing Effects

When the Bypass Effects option is enabled, effects processing will be disabled for the specified application or output device. This makes it possible to quickly toggle between an active or disabled effects configuration. Note that the On/Off state of each individual plugin will remain unchanged.

When Bypass Effects is turned on, a warning indicator will be shown to indicate that effects processing is disabled.

As indicated, effects on the Music app are being bypassed

To access the Bypass Effects setting, control-click the application or Output Device in the main window. The resulting contextual menu will include a Bypass Effects option which you can toggle on or off. In addition, when an application or the Output Device is selected in SoundSource, pressing Option-Command-B will toggle this option.

Advanced Notes on Audio Flow

Audiophiles may be curious about the exact pipeline through which audio flows when using SoundSource. Audio first flows through any per-app adjustments which are configured, and then through any System Output Device adjustments.

Within a single effects area, audio is adjusted by each plugin in sequence, moving from top to bottom. There is one exception, however: the Volume Overdrive effect. Regardless of the location of this effect, it is always applied last.

Per-App AdjustmentsMenu Bar Controls