Lossless music:
which to pick?
AAC, ALAC, bits, kHz: is higher always better?
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The full narration of the video.
Same song: the basic setting is around eight megabytes. The top Hi-Res Lossless setting is over a hundred. Can your ears hear ten times the size? Recorded sound is huge, so it always gets packed down. There are two ways. One is like a vacuum storage bag: suck out the air, open it, and it puffs back exactly as it was. That's lossless. Apple's is called ALAC; elsewhere it's often FLAC.
The other is like tossing stuff when you move: a whisper drowned out by a noisy restaurant, you'd never hear it anyway. So out it goes. The file shrinks to about a fifth. That's lossy. Apple's is called AAC. The kbps on the menu is how much data each second uses. A CD uses 1,411. Apple's AAC uses 256. A 2009 study in Canada: trained ears could still hear a difference at 192. Above that, it gets hard to tell.
Next, kHz. Sound is air shaking. Recording means measuring, many times a second, how far it has shaken. 44.1 kHz means 44,100 measurements a second. The highest note it can capture is already above the twenty thousand our ears top out at. And we hear less as we age. What 192 kHz adds, you mostly can't hear.
Bit depth is how fine the ruler is. Sixteen bits gives over sixty-five thousand steps. From a silent bedroom at night to a drill at your ear, it all fits. Twenty-four bits is finer, and useful in the studio. But at your ear, the extra steps are quieter than the noise in your room. In 2007, American audio fans ran 554 blind tests. High-res against CD: people were right less than half the time, about a coin flip.
Some studies say trained listeners can tell a tiny bit; the evidence is still debated. The biggest trap in your gear is Bluetooth. Apple says it plainly: Bluetooth connections aren't lossless. Headphones like AirPods squeeze the song back into AAC on the way.
So with ordinary Bluetooth headphones, lossless never reaches your ears. Plug in a cable. Or use a phone and headphones that both support lossless Bluetooth. Above 48 kHz, an iPhone needs a little external box to turn the data back into sound. The app needs lossless switched on. Chinese apps usually want a membership. So how to choose? With Bluetooth headphones, the AAC setting is enough. With a cable, pick CD-quality lossless. 16-bit, 44.1 kHz, and you've hit the limit.
Bigger numbers cost data and storage, and your ears mostly can't catch the rest. Don't believe it? Try this: have a friend switch between two settings at random while you guess ten times, eyes closed. How many did you get right? Come back and tell us.
Same song,
ten times the size
The same song is about 8 MB at your music app’s basic setting, and over 100 MB at the top “Hi-Res Lossless” setting.
More than ten times bigger. Can your ears tell? Let’s take the menu apart, one name at a time.
Vacuum bag,
or throw stuff out
Recorded sound is huge, so it always gets packed down. There are two ways:
kbps:
data per second
The smaller the number, the more gets tossed. In a 2009 study in Canada, trained ears could still hear a difference from CD at 192; above that, it got hard to tell.
Apple Music’s default “High Quality” setting is AAC 256.
kHz:
measurements per second
Sound is air shaking. Recording means measuring how far it has shaken, many times a second, like burst-mode photos.
So what 96 or 192 kHz adds is mostly sound you can’t hear.
Bits:
how fine the ruler is
At your ear, the extra 24-bit steps are quieter than the noise already in your room.
Blind tests:
about a coin flip
The biggest trap:
Bluetooth
Apple says it plainly: Bluetooth connections aren’t lossless. Headphones like AirPods squeeze the song back into AAC on the way.
With ordinary Bluetooth headphones, lossless never reaches your ears.
So,
how to choose
16-bit, 44.1 kHz
Bigger numbers cost data and storage, and ears mostly can’t catch the rest. “Master” tiers on some apps are mostly the app’s own processed versions; let your ears decide.
but most ears
can’t tell.
Quick check
You turn on “Hi-Res Lossless” while wearing ordinary Bluetooth headphones. What happens?
Bluetooth isn’t lossless: the vacuum-packed song gets “thrown out” and squeezed again on the way.