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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."
A quick note about dynamic range, which is what the bit depth affects.
Maximum dynamic range that human hearing can discern: 140dB average
Maximum practical dynamic range of CD: 90dB
Maximum practical dynamic range of 24-bit audio: around 140dB
Dynamic range required for full range live music playback, according to Ampex: 118dB average
Maximum practical dynamic range of high quality studio analog tape: 80dB
Maximum practical dynamic range of studio analog tape in the '60s: ~70dB
So, if you have a piece of music recorded, mixed, mastered and released in pure 24-bit depth, you *may* hear a difference under ideal conditions (excellent production, good equipment, *quiet* listening room, etc...) Note that there have been double-blind listening tests of SACD, and listeners were unable to hear a difference between the CD version.
All those old Beatles and Rolling Stones albums? Keep the best CD version you have, more bits aren't going to make a difference.
My Other Computer Is A Data General Nova III.
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.
The use of more dynamic range is it's increase in the signal to noise ratio....or reduction in quantization noise: the stair step of digital audio. In 16bit audio, the minimum step between levels is 1/65535 of full loudness. For the same listening level, with 24bit, that goes to a ridiculously small 1/16777215, or 256 times less. This pretty much making quantization noise negligible for the whole recording to delivery workflow if you're pumping the signal up to any reasonable power level.
>>>grossly overcompressed and far worse quality than the old analog video
Many cable companies squeeze 10 SD channels into the 6 megahertz space. That's about Mbit/s so of course they look like crap.
I use an antenna now to get HD and SD channels directly off the air, and at no charge. Cool stuff like a free movie channel, RetroTV, AntennaTV, Megahertz, and so on. Plus the Big 7 networks of course.
Information wants to be expensive AND wants to be free. So you have Value vs. Cheap distribution fighting each other.
There are already floating point standards for audio. 32-bit, 48-bit, and 64-bit formats. When recording I typically record to 24-bit integer, but everything beyond that runs at 64-bit (all the processing). There's an amazing freedom moving to a well-implemented 64-bit audio stack for mixing, because it lets you go over 0db (ie past the digital clip point for integer level stuff) and drop the level down in a bus (like a collection of all 12 - 16 mic tracks), instead of having to carefully level all of those tracks (and every track really) so that at no point does the audio signal ever get too hot, checking the level between every single plug-in you use. It's a wonderful freedom that makes making music easier. But as a commercial distribution format, that would seem to be really REALLY overkill. Those formats, to my knowledge, are pretty much exclusive to the recording world (though Windows uses floating point audio for mixing everything in Windows Vista and Windows 7)
For at least a decade already, the industry standard has been 24 bit recording hardware, and 32 or 64 bit mixing software.
Even the cheapest pro audio recording interfaces are 24 bit. http://www.m-audio.com/
This is the stupidest thing I've heard in a long time.
16 bits per channel gives you a whopping 96dB or so of dynamic range.
All popular and contemporary music has crap compressed out of the dynamic range so you'd be lucky if you could get a discernable 20dB of range. Classical music needs a lot more, but not 96dB. Maybe 60 or 70dB.
You would need as quiet a listening environment as an empty concert hall, and a very high powered amp turned up loud, to even hear as much dynamic range as is represented by 16 bits.
And they think adding more even dynamic range than that is a good idea?!
If they wanted to make a difference to sound quality, they should increase the sample rate to 48kHz, or hey go why not crazy and go to 96kHz. It will still not sound any different to the average person, but at least the difference can actually be detected and measured with the right equipment.