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Apple in Talks to Improve Sound Quality of Music Downloads
Barence writes "Apple and music labels are reportedly in discussions to raise the audio quality of of the songs they sell to 24-bit. The move could see digital downloads that surpass CD quality, which is recorded at 16 bits at a sample rate of 44.1kHz. It would also provide Apple and the music labels with an opportunity to 'upgrade' people's music collections, raising extra revenue in the process. The big question is whether anyone would even notice the difference between 16-bit and 24-bit files on a portable player, especially with the low-quality earbuds supplied by Apple and other manufacturers. Labels such as Linn Records already sell 'studio master' versions of albums in 24-bit FLAC format, but these are targeted at high-end audio buffs with equipment of a high enough caliber to accentuate the improvement in quality."
Perhaps is music wasn't overly compressed (talking about dynamic range, here) they wouldn't need so many more bits of resolution for the -3 dB they're mastering audio at these days.
More Twoson than Cupertino
Not really, although possibly, depending on the recordings. The difference between 24-bit and 16-bit audio is the dynamic range, with 24-bit having a much wider range between the quietest possible sound and the loudest possible sound. This is something that can definitely be heard, even on lower end equipment.
16-bit audio has a 100dB dynamic range and if properly dithered from 24-bit to 16-bit almost no one will notice the difference. To claim otherwise is to fly in the face of ABX tests which back this up.
Apple already sells Apple Lossless files so that's a non-issue. If Apple *actually* wanted to improve the quality of music they would demand remastered tracks with actual audio engineers doing the work instead of rap "producers" using the compression widget in Protools to make it sound "better".
There are 4 boxes to use in the defense of liberty: soap, ballot, jury, ammo. Use in that order. Starting now.
128kbit/s at 24-bit! Now excuse me while I crank it to 11.
CD have more then enough dynamic range, it's just that it is hardly ever used.
Analogies don't equal equalities, they are merely somewhat analogous.
Right.
I've been in the auditorium at Dolby Labs in San Francisco, which is set up for high quality audio. (The entire room is vibration-isolated from the rest of the building and soundproofed to the point that external noise is essentially zero. The audio gear is, of course, good.) In there, 24 bit audio with full dynamic range can be clearly distinguished from 16-bit audio on orchestral music. The soft passages don't get that awful 4 to 6-bit sound quality when the high bits are all zero.
Through earbuds, on the street, or in a car, no way can you detect that difference in quality. For rock, it doesn't make sense. Hip-hop could probably be clipped at 8KHz without much loss. As long as you had enough speaker power for the bass nobody would notice.
If you don't think there is real high end equipment it just means you've never looked/listened. I'm not taking $1000 speaker cables or other such snake oil, I'm talking high end speakers and so on.
Speakers in particular have a wide range because they are almost always the worst component of a system. An amp that has THD in the fractions of a percent may be hooked in to a speaker that has THD in the 5-10% range when played at a high volume.
There can be a pretty big difference between normal and good equipment. There's also a pretty big monetary difference so it isn't worth it for everyone, but if you like good sound, maybe it is. It also isn't something magical that you have to have faith exists, it is stuff you can measure. Flatter frequency response, lower THD, lower noise, better dispersion, etc, etc.
Now, does that mean 24-bit is useful? Eh, I dunno. In theory possibly. You get 96dB of dynamic range out of 16-bit audio. You can extend that through dithering, but at the cost of raising the noise floor. Human hearing is more in the 120dB range. 0dB SPL (20 micropascals) is chosen as 0 becuse it is roughly the threshold of human hearing. Some people can hear a little below that, many cannot hear that low because of hearing damage/loss. 120dB SPL is about the level where you start to feel immediate pain and thus going past it is not recommended.
So to fully cover the human range of hearing you'd need 20-bits, but then more can be useful because of course if you are trying to represent low level sounds with just 1 or 2 bits, they are going to have rather bad quantization artifacts. Again dither can deal with this, in trade for higher noise levels, but just going 24-bit solves it.
As a practical matter though, it is of questionable usefulness. For recording it is quite useful because it allows for headroom. You want to be able to have plenty of digital headroom (to prevent clipping), but still capture all the detail. However when you mix everything and normalize it down, that's not so important. It also takes some fairly high quality equipment to start getting 100dB or more of actual effective SNR and dynamic range out of a system, not to mention a rather quiet room. You can hear sounds below the room's noise level, but only maybe 10-15dB below.
I've played with it quite a bit since audio production is a hobby and I really can't form an opinion. I can set up tests where I can hear the difference, but I can set up tests where I can't.
Over all I think it would be nice to move to 24-bit since space is rapidly becoming a total non-issue and it just avoids it ever being a problem. Kinda like moving past 8-bits per channel for video. However I don't think it is a big issue and it isn't something I'll tell people they gotta have. "CD quality" has endured precisely because it is "good enough" for most things. Maybe not perfect, but you don't really notice any problems in normal use and that's what matters.
You will still experience better sound quality with a 16-bit CD than with 24-bit FLAC files.
This is because CDs are recorded and played back with lasers, meaning they are essentially an analog medium, because light is analog.
FLAC files, on the other end, are made of bits - sharp little bastions of absolute certainty, having a value of either or one, with nothing in between.
So, in essence, while CDs are recorded in analog bits, whereas FLAC files are recorded with digital, electronic bits. This means that CDs will sound better, because each bit is closer to the original recording; and, remember, that the whole is even more than the sum of it's bits!
PS: Make sure you orient your Monster Cable wires in the appropriate direction to maximize electron flow! There should be an arrow on the insulation pointing toward the speakers.
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