skamp
Aka: HeadFiend, BatFi
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16 bits * 44100 samples per second * 2 channels = 1411200 bits per second
There is a remarkable resemblance to full-resolution at that bit rate, to be sure. However, at least for me, longer listening (esp. on a familiar system when the subject is selecting the music and volume) reveals that differences can be heard up to 320kbps. Double blind methodology matters -- to do it well is seemingly impossible, and lengthy. When DBT does in fact detect a difference, you have a strong positive result. However, when it does not reveal a difference, by definition ("null hypothesis" testing), nothing is proven except that the difference is not large enough to be obvious under those exact conditions.
hile there is certainly excessive self-fulfilling or placebo effects in the high-end world, it is not universal. I have been an AES member and even published a few times, and over the decades I've studied Sean Olive, Floyd Toole, and others, and been friendly with John Curl and John Atkinson. And spent some time with Mikey, and a dozen manufacturers and journalists. A major mentor was Richard Heyser. The ones who know what they are doing do not often fall prey to that. At least speaking for myself (acoustician and audio consultant for a time, who has studied with James Boyk at Caltech, Isadore Rudick and others at UCLA, and was offered the job of technical director at Stereophile in 1988), I tend to be hesitant to conclude any differences exist unless I can double check myself (like an informal version of the formal replication required in science journals.) Turns out, BTW, that my wife hears differences even faster than I. I could tell stories!....
16/44.1 WAV or AIFF from CD rip is effective 1411kbps, no redundancy there in the meaning of error correction.
some music doesn't have enough definition for it to be detected. But if I listen very closely, there are parts of certain tracks that give it away.
...
And if he is able to push better work in the studio when the files are produced, then this will be a win for us. Give me a 320k MP3 produced correctly any day, and I will be a happy camper.
AIFF is 1411kbps, as you say. Apple Lossless is variable bit rate, about 800-900kbps. By definition, any higher bit rate than a lossless format is "inefficient" for some reason or another. So it is not a good comparison quantitatively to mp3 which is intended to be ultimately efficient.
But, perhaps I'm recalling poorly when I said that AIFF is what is exactly what is in the CD pit by pit. I do know that the CD pits include additional bits and spatial arrangement of the data to better cope with scratches, dust, laser wavelength, etc. So, accepting the math, that implies that the bit stream from the CD itself is higher than 1411bps, some of which is not necessary for the music encoding alone:
http://en.wikipedia.org/wiki/Eight-to-fourteen_modulation
Under EFM rules, the data to be stored is first broken into 8-bit blocks (bytes). Each 8-bit block is translated into a corresponding 14-bit codeword using a lookup table. ... Thus, in the final analysis, 17 bits of disc space are needed to encode 8 bits of data.
http://www.webopedia.com/TERM/E/Eight_to_Fourteen_Modulation.html
Eight-to-Fourteen Modulation, or EFM as it is abbreviated, is an encoding technique used by CDs and provides a way of countering errors by encoding abyte into 2 bytes. Using EFM the data is broken into 8-bit blocks (bytes). Each 8-bit block is translated into a corresponding 14-bit codeword using a predefined lookup table. The 14-bit codeword are chosen so that binary ones are always separated by a minimum of two and a maximum of ten binary zeroes.
Originally Posted by Stoney /img/forum/go_quote.gif
But, perhaps I'm recalling poorly when I said that AIFF is what is exactly what is in the CD pit by pit.
Yes you are. It isn't. Just 16/44.1 PCM data comes off the CD.
Hey, their off topic banter is more action than this thread has seen in awhile,...enjoy it.