MacBook Pro/Air Plug-In Chime: How to Enable It

Enabling the Power Chime on MacBook Pro and Air

Introduced with the MacBook in 2015, a distinct chime sound plays upon connecting the device to power, mirroring the behavior of iPhones and iPads.

However, this functionality isn't automatically activated on MacBook Pro and MacBook Air models.

The Hidden PowerChime Feature

Despite being disabled by default on Pro and Air models, the PowerChime.app, responsible for generating this sound, is already installed within macOS across all Mac computers.

Activation requires executing a single command through the Terminal application.

Benefits of Enabling the Chime

For users with worn charging cables or those experiencing issues with loose power outlets, the chime provides audible confirmation that a connection has been successfully established.

This can be particularly useful in ensuring a reliable power supply.

Credit for discovering and sharing this technique goes to GitHub user herbischoff.

• The chime sound is standard on the 2015 MacBook.
• MacBook Pro and MacBook Air require manual activation.
• PowerChime.app is pre-installed on all macOS systems.

Hearing the chime can offer peace of mind regarding your charger's functionality.

Activating PowerChime on MacBook Pro and Air Models

The PowerChime.app can be activated by utilizing the Terminal application. Access the Terminal through Applications > Utilities, or by initiating a Spotlight search for "Terminal".

Subsequently, copy and paste the following command into the Terminal window and press the Enter key:

defaults write com.apple.PowerChime ChimeOnAllHardware -bool true; open /System/Library/CoreServices/PowerChime.app &

While commands may initially appear complex, their functionality is quite straightforward. Let's dissect this specific command:

• The term defaults represents a macOS utility designed for modifying system settings.
• write instructs the defaults program to implement a change.
• com.apple.PowerChime ChimeOnAllHardware -bool true designates the precise setting to be altered.
• The semicolon ; serves as a delimiter, concluding the first command and initiating the subsequent one.
• open directs your Mac to launch a specified application.
• /System/Library/CoreServices/PowerChime.app identifies the PowerChime application itself.

Upon successful execution of this command, an audible chime will be emitted each time your MacBook Pro or Air is connected to a power source. This provides a convenient confirmation of power connection.

This feature can be a useful indicator, especially in situations where the visual charging indicator is obscured.

Understanding the Command's Functionality

The defaults write command modifies a preference setting within macOS. In this case, it enables the chime sound for all hardware configurations.

The open command then launches the PowerChime application, ensuring that the new setting takes effect immediately.

Deactivating the Power Chime on MacBook Pro and Air Models

Should you wish to revert this change, the following command will restore the original Power Chime functionality:

defaults write com.apple.PowerChime ChimeOnAllHardware -bool false;killall PowerChime

This instruction closely mirrors the previous one, differing only in the use of false rather than true.

The subsequent command, executed after the semicolon, terminates the PowerChime.app process instead of initiating it.

Essentially, this process allows users to easily toggle the system chime on or off based on their preference.

Understanding the Commands

The defaults write command modifies a system preference setting. Specifically, it alters the ChimeOnAllHardware key within the com.apple.PowerChime domain.

Setting this key to true enables the chime, while false disables it.

The killall PowerChime command then ensures the change takes effect immediately by restarting the PowerChime application.

• Defaults Write: Modifies system preferences.
• ChimeOnAllHardware: The specific setting controlling the chime.
• Killall PowerChime: Restarts the application to apply changes.

These commands provide a straightforward method for customizing the auditory feedback provided by your MacBook Pro or Air.

Re-enabling Power Chime

To reactivate the Power Chime, simply execute the following command in Terminal:

defaults write com.apple.PowerChime ChimeOnAllHardware -bool true;killall PowerChime

This command sets the ChimeOnAllHardware preference back to true, and then restarts the PowerChime application.

This will restore the default system chime behavior on your MacBook.

The Rationale Behind the Charging Sound

The inclusion of this seemingly minor setting stems from a specific need related to the 2015 MacBook model.

This particular MacBook transitioned to utilizing USB Type-C for charging, a departure from the Magsafe charger traditionally employed in the MacBook Pro and Air series. The Magsafe connector is widely regarded as a successful Apple innovation, notably featuring a visual indicator to confirm a secure connection.

However, the USB Type-C charger supplied with the 2015 MacBook lacked this visual confirmation. Consequently, users required an alternative method to quickly verify that charging was actively occurring. The audible charging sound was implemented to address this requirement.

The reasoning behind not simply retaining the Magsafe connector in the newer MacBook remains unclear, yet the functionality of the sound extending to other Apple devices is a welcome benefit.

Image courtesy: MarLeah Cole/Flickr