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The Rise of "Hybrid" Vinyl-MP3s
Khyber writes to let us know that First Word Records, a U.K.-based record label, is now selling vinyl records that come with codes that allow you to download a 320-kbit MP3 of that record's content. The article mentions another independent label, Saddle Creek, that also offers DRM-free downloads with some vinyl records. The co-founder of First Word is quoted on why they didn't DRM the download: "Making a legal, paid-for version of the file less useful than a copied or pirated one doesn't make sense."
Of course, expading the "doesn't make sense" part is important. It's also critical for the surely-to-be analogizers below to realise that this has no usefulr real world (as in, tangible) comparison. If three clicks of the mouse provides you with something far more useful than something you've shelled out your hard-earned cash for, something is wrong. Lax enforcement -- not to mention the difficulty of enforcement -- and fuzzy laws make this so.
It's not as easy as saying, "Stealing a car has more utility than buying one, we should all steal cars!" since enforcement and history are so vastly different. See, the car analogy is wrong! Ha!
Sony ha
Don't they realise that evil hackers will make multiple copies from the vinyl to audio cassettes and listen to it on portable tape players? Home Taping Is Killing music!
They whose government reduces their essential liberties for temporary security, receive neither liberty nor security.
It's an ancient musical recording that is etched into a circular rock. A bird presses it's beak to the stone and rotates it, producing sound.
Badass Resumes
Yes. Nyquist. There's a Theorem, a Limit, and a Guy that discovered these, all by the same name.
A 44.100kHz sample rate will theoretically get you up to a 22.050kHz max frequency in the audio signal. Humans can focus on any part of the audible spectrum, but voices won't typically fall outside the 300-3300 Hz range. Thus aLaw (US) and mu-Law (outside the US, a.k.a. "uLaw", since the Greek mu looks like a u with a tail) are typically 8000 Hz sample rate, 8-bit-sample, monophonic (who has a stereo telephone?) signal when digitized.
The GP was worried that the bit depth is "coarse". This is not the case. Bit depth "distance" is constant for a given depth.
CD's are 44.1kHz, 16-bit, stereo. Always. So there are always 44100 samples per second per channel. There are always two channels (stereo, one left, one right). And each sample in each channel is always 16 bits. A 16-bit integer can represent numbers from 0-65535 (2^0-1 through 2^16-1), and since there's no need for negative numbers (this is Pulse Code Modulation, or PCM, so no, you don't need to represent a +/- of a waveform) you get the full 0-65535 swing. From there, the value is directly translatable into a DC voltage that goes to the speakers. (Most of the heavy lifting is done in the A/D phase, D/A phase is a simple value-to-DC conversion.) The change in DC voltage over time is what causes the magnets to move, which moves the speaker cones, which moves air, which moves your tympanic membrane, which blah-blah-blah... eventually you hear sound.
So there's no need to worry. Nothing gets coarse. Nothing loses fidelity. Nothing loses audible quality. This is why vinyl fanatics get laughed at by people who know how and why digital audio works. The limits of even now-mundane CD audio are far above the possible limits of even hypothetically perfect human hearing. Nobody can hear 22kHz. Nothing below 22kHz is misrepresented in CD-quality audio. For mastering work, where effects will be applied later, higher quality recordings are wonderful, since you can guarantee that it will stay high-quality when downsampled to CD-quality, but other than that (and "economies of scale" where better parts are just as cheap to produce), there's no need for anything better.
You are correct, the Nyquist theorem states that you must record at a sampling rate that's above twice the higher frequency in your recording.
All this debate over vinil is rather tiresome. Anyone who has studied electronics engineering like I did knows that vinil records have a rather low signal-to-noise ratio. I did a course on "Probabilistic Models in Electric Engineering" where we learned how to calculate noise due to the fact that electric charge is quantized. Now, get this vinil fans: ELECTRIC CHARGE IS QUANTIZED. There is no such thing as a charge smaller than an electron, which is 1.6e-19 coulomb.
There are no such thing as analog values in this universe, everything is quantized. You cannot possibly have an electric signal that's totally free of noise, what you get is a number of "clicks", one for each electron that goes by. The same way, you cannot even hear a sound without noise, what you get is a number of "plocs", one for each air molecule that hits your eardrums.
Now, I know people will say, "sure, but these effects are very small". Well, think again. Human hearing evolved to be as sensitive as it physically could be. Inside an anechoic chamber you can hear the blood flowing through your veins. The sensitivity of our ears is just short from hearing individual molecules hitting the eardrum. In any analog pick-up, be it moving coil or moving magnet, human ears are sensitive enough to hear the noise due to the quantization of electric current.
Digital equipment have much better signal-to-noise rations because they have high currents in low-impedance circuits, the effect of charge quantization is diluted by averaging a large number of electrons. In analog vinil pick-ups either the impedance is relatively high for moving magnet models or the voltage is very low for moving coil types.
And all this is considering only the most fundamental effects, not to mention problems as dust on the record. The cleanest cleanroom specified in the ISO-14644 standard has 12 particles per cubic meter. The lowest spec in ISO-14644 allows over 40 million particles per cubic meter. Does the room where you do your listening conform to an ISO "cleanroom" specification?
Digital sound standards were created to be as good as they need to be. CDs have all the bandwidth and dynamic range one needs in the final recording. It's only when you are going to mix and resample the music that you may need better quality to avoid round-off error in the processing. Because of this, professional equipment normally use something like 24 bits @ 192 kbps. The widespread acceptance of MP3s show that the CD standard has actually a better quality than the majority of people need or want.
here is an illustration
------ hi mom
It's turtles all the way down.