It’s a cheesy bit of trivia to be sure. Facebook’s ping sound–the alert you might hear if you receive a Facebook video call–is built from an Fmaj7 chord. That means the notes are actually F, A, C, and E–which obviously spells FACE. Heh.

This little tidbit, shared by Facebook’s early brand designer Everett Katigbak on Quora, will only lead you to ask more questions: Why these notes? Why this sound? Well, it’s not just a random chord that’s easy on the ears. The motivation was to induce the feelings of familiarity and nostalgia. From Katigbak:

The intervals are 2 major thirds, F-A, and C-E. The major third trill is what is used on old school telephones. There were several iterations on this, but the first instance where the chord was used, was as the video calling inbound ringtone. It is the base arpeggio in two pulses: F-A-C-E, F-A-C-E. We went with the two pulses because this resembles a majority of international ring variations. It also contains a minor 3rd interval, A-C. Descending, this interval is the same used in the common doorbell (ding-dong), which conceptually reminded me of when a friend would show up at your house. It is also the quintessential “DIINNNNEERRR” or “LAASSSIIIEEE” call out, which again, is a very nostalgic pattern.

In other words, Facebook’s ping is like an Instagram filter for your ears.

Apparently, the Fmaj7 chord is part of a “modular suite” of sound for Facebook to riff on across their brand. And now that our ears are alerted to it, I wonder where else we’ll hear FACE cropping up. Because sonic branding is a powerful tool, but its potential can be reached only if it’s deployed everywhere from our Facebook notifications to Facebook’s live events. With enough commitment, FACE could be every bit as identifying as the company’s logo, but in a far more subtle way–leading us, at will, to a Pavlovian response evoking images of promotions, engagements, newborn babies, and our most cherished dinners with friends.

Or, you know, maybe just Grandpa’s latest bigoted rant.

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