Personal computers with Windows have made sounds to indicate errors since the 1980s. With Windows 11, Microsoft has revamped those sounds to make them less stressful.

Windows remains the world’s most popular operating system, accounting for about 14% of Microsoft’s $168 billion in annual revenue. But it isn’t always easy for Microsoft to keep its hundreds of millions of customers happy, as they have widely varying opinions of what Windows should be — including what it should sound like.

The designers of Windows 11 took inspiration from an approach called calm technology, which was described by two employees of the Xerox PARC research lab more than two decades ago. “Calmness is much needed in today’s world, and it tends to hinge on our ability to feel in control, at ease, and trustful,” Microsoft’s Christian Koehn and Diego Baca wrote in a blog post. “Windows 11 facilitates this through foundational experiences that feel familiar, soften formerly intimidating UI, and increase emotional connection.”

Calm technology also informed the development of the sounds of Windows 11, said Matthew Bennett, who crafted the sounds, following contributions to Windows 8 and Windows 10.

Windows 11 stands out from its predecessors and its competitors by allowing people to use one group of sounds to match with light visual themes, and a different group that goes along with dark themes. The sounds are similar, which means people can recognize them as they switch between modes, but slightly different. Applying a dark theme generally makes the sounds softer. They seem to echo, as if in a large room.

“The new sounds have a much rounder wavelength, making them softer so that they can still alert/notify you, but without being overwhelming,” a Microsoft spokesperson told CNBC in an email. Just like we rounded UI [user interface] visually, we rounded our soundscape as well to soften the overall feel of the experience.”

People can change the default sounds by opening the Settings app and going to “Sound > More sound settings.” But plenty of people will keep using the default sounds, just as many people who open Microsoft Word will end up using the default font.

Bennett, who left Microsoft in February after 12 years at the company, spelled out several changes the company made to its system sounds with Windows 11 during the course of multiple interviews. (Each of the audio files below contains the new sound, followed by its Windows 10 predecessor.)

When something goes wrong — for example, you look for text on a website and it isn’t there — and your PC needs to give you a heads up, Windows 11 won’t make as much of a fuss as Windows 10. The new sound, comprising three rising notes, starts at a lower pitch than the trill that it replaces, and it doesn’t linger as long afterward, Bennett said.

The notes aren’t simply played by a piano or marimba. Bennett said the sounds are “digitally sculpted” and designed not to evoke a musical instrument. That way, they’re less likely to get negative associations in various cultures around the world, he said.

Four rapid ascending notes let you know an event is coming up. The arrangement is vastly simpler than the seven-note predecessor, which Bennett has described as having a clear beginning, middle and end.

After Windows 10 arrived in 2015, people ran it in schools and offices, where background noise could deafen some of the Calendar Reminder sound. Then the coronavirus pandemic forced workers, teachers and students to stay home, where there might be fewer distractions. The new sound demands less attention in those environments.

When you receive an email in Windows 11, you hear three quick notes going downward. The new version is slightly faster — the one in Windows 10 included four notes and sustained for a moment at the end — and registers a lower pitch.

It’s more of a gesture, reminiscent of a piece of mail arriving in an inbox, and less of a voice-like snippet. “I read it as, “Message for you,'” Bennett said.

These areas of the next generation of Windows refer back to the stripped-down effects that appeared in Windows Vista and remained available in Windows 7, Bennett said. Anytime you plugged a mouse, a joystick or another peripheral into a USB port, or removed it, or the computer didn’t recognize the device, those 2000s-era operating systems made two abbreviated, guttural noises.

Windows 10 veered from that concept a bit with additional notes and varying melodies. Each of the Windows 11 sounds goes back to the idea of two simple notes, albeit in a more friendly fashion than their predecessors from the 2000s.

An upward tone conveys that the connection worked.

Going down means you’ve successfully unplugged.

And two sounds imply an error, sort of like how parents who speak a variety of languages will quickly say “uh-uh” to warn their children not to do something, Bennett said.

Sounds for calendar events and emails can play frequently on Windows PCs, but sounds that indicate new instant messages are far less frequent, Bennett said.

But they’re still there, and in Windows 11, they’re simpler. Three descending notes go off to mark a new message, instead of a chirp that goes up and then down. The Windows 10 message sound was meant to stand out from the mail sound to reflect the different rhythm of messaging, Bennett said. Now that distinction is more subtle.

The point of the Message Nudge is to signal the arrival of a new message coming in through a program that’s you’re currently using, but perhaps in a different conversation, Bennett said. In Windows 11 you hear one note and then a slightly lower note. It’s shorter than the sharp Windows 10 sound, which amounts to a miniaturized version of the Instant Message Notification sound in that operating system.

This sound, which comes up in concert with certain “system toast” boxes on the side of the screen, has also received a makeover. There are two slightly ascending notes that are close together, instead of four notes that rise and then fall. The sound is shorter, and the final note isn’t sustained for so long.

When a program asks for permission to make changes to your PC, Windows 11 shows a prominent dialog box on your screen and plays a sound. The outcome can have security implications, hence the notification.

In Windows 11 the sound is an up-down-up pattern that comes in at a lower pitch than the down-up-down chime. It’s less all-hands-on-deck and more you-might-want-to-check-this.

So far, much of the new feedback on the new sounds has been positive, after Microsoft began circulating Windows 11 builds to testers in June.

The company will release Windows 11 more widely later this year.

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