AirPods Pro, like the ears in which they reside, typically come in sets of two. One in the left ear, the other in the right. T'was ever thus. (It's what makes AirPods Pro one of the best earbuds on the market today.)
It's not uncommon to see someone wearing just a single earbud. Maybe that's just their preference. Maybe they need to be aware of their surroundings and want to keep one ear free. Or maybe they only have one ear. But the bottom line is, you don't need a reason. If you want to wear a single AirPod, go ahead. We're not here to judge.
However, if you're using a single AirPod Pro and want to activate the active noise cancellation (ANC), it's turned off by default and won't turn on with the usual squeeze of the stem.
Turn on ANC for a single AirPod Pro earbud
Having ANC turned off when you're only using a single AirPod Pro is by design. But if you really want to have one ear open while the other has ANC turned on and the world tuned out, here's how to do it.
Step 1: Turn on your AirPods Pro either by opening the case or by inserting at least one into your ear.
Step 2: On your iPhone or iPad, open the Settings menu.
Step 3: Select your AirPods Pro.
Step 4: Scroll down (way down) and head into the Accessibility section.
Step 5: About halfway down (you may have to swipe depending on your text size), you'll see Noise cancellation with one AirPod. Turn the toggle on.
And that's that. You'll now have one ear with active noise cancellation. The other ear is left free to roam about the world, burdened by the din.
There's likely a very good reason this is turned off by default — it's definitely a little weird. But having an option is better than not having an option, so you can feel free to turn it on if you want.
