Add a Startup Audio File?

You are correct that Apple no longer provides a native way to inject custom audio files directly into the root boot sequence. Because modern macOS versions utilize a strictly locked, cryptographic Signed System Volume (SSV) to secure the operating system, modifying root system triggers or firmware-level behavior is no longer possible.

You can still achieve a similar user experience using a modern workaround that fires your audio file immediately after your user account logs in. 

The workaround relies on the built-in Shortcuts app (which has fully replaced Automator in modern macOS) combined with Login Items. To do that, you would need to:

• Use the Shortcuts app to create a shortcut to play the sound
• Turn that shortcut into an app using the Shortcuts app
• Set that app to launch on login by adding it to the Login Items

Even so, it would play at login not right after the startup chime. Of course, you could disable the startup chime (System Settings > Sound, set Play sound on startup to OFF). But it would only play close to the startup if you also set up automatic login (which IMO is a horrible idea from a security standpoint, and not possible with FileVault enabled which is a very good idea from a security standpoint).

The above may not be worth the effort, but Apple provides these resources on using Shortcuts and adding a Login Item.

Shortcuts User Guide for Mac - Apple Support

Change Login Items & Extensions settings on Mac - Apple Support

neuroanatomist

Thanks very much for the details! I went back to one of the 'how to' from a few years ago just to play around with it and used Automator - which is still in my Apps folder and apparently still working in OS27. And it worked! I'll update it to Shortcuts in a few days. Anyway, you're correct, it doesn't trigger right after the chime, but close enough for my purpose: "Ahhh, I see you have a machine that goes binggg!"

Thanks again!

homeden wrote:

Any idea how to add a startup sound to a MacMini running OS 27?

Apple used to allow an audio file (ie, .aiff) to be added to a Mac's startup process - right after the startup chime played you could add/play another sound. It appears it's no longer available, but I thought I'd check if anyone knows if there's a workaround. I've come across a few articles, but those are from a number of years ago and relied on setting up either an Automator script or adjusting Terminal code.

Thanks.

Have not heard of this as an option for years, if not a decade...

To be proactive you can submit your feedback here: Feedback - macOS - Apple

Glad you got it working!