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Digitizing Rare Vinyl
eldavojohn writes "While the RIAA is busy changing its image to a snake eating its own tail, one man is busy digitizing out-of-print 78s. 'There's a whole world of music that you don't hear anymore, and it's on 78 RPM records,' he stated to Wired. Right now, you can find about 4,000 MP3s on his site, with no digital noise reduction implemented yet."
I was expecting someone putting a record into a flatbed scanner
That's been tried, and it sort of works. But ordinary scanners don't have enough resolution. The Library of Congress has a scanner that does. They image the disc at a resolution of 1 micro per pixel, which yields 8 GB or so of imagery. Then they have software which can reconstruct the audio from the image.
Not only is this useful for fragile, unique records, but it will work on cracked or scratched ones. It's even possible to reconstruct a broken record if you have all the pieces.
The current scanner only works for horizontal recording; it can't read depth. So it won't work on vertically recorded records (Edison) or stereo (45/45 Westrex has two components 90 degrees apart.) They're working on that.
And another part too...
The 78 RPM records weren't on Vinyl - it's Shellac, which is a lot more sensitive than Vinyl.
If builders built buildings the way programmers wrote programs, then the first woodpecker would destroy civilization.
That was pretty brilliant of the record companies, though, don't you think? Make the medium out of nice, soft vinyl, and make the worthless, replaceable needle out of the hardest mineral on the Mohs scale.
Brilliant, that is, if you want to maximize the rate at which the media wear out.
I have mod points right now, and this post makes me wish there was a "-1 ignorant" rating.
You must be new here. Or at least not tech-savvy or young enough to never have thought about these things.
If you want to minimize wear between two friction surfaces the WORST thing to do is to make them both out of the same material. The best is to make one hard and the other soft. I don't know why this is true, but perhaps someone more versed in mechanical engineering and materials science can explain. In watches, for example (mechanical ones), the jeweled bearings you hear about are typically a sapphire or ruby (synthetic) cone in which a metal (steel or brass) pin rotates, not gem-against-gem. So diamond-against-vinyl makes sense (hard against soft). And not all phonograph needles were diamond; that was a relatively late phenomenon.
But far more important is how the medium -- the record itself in this case -- is manufactured. In some cases they were injection molded (rare), but more often they were pressed. Now think for a second, how are you going to make records, and do it inexpensively enough that you can sell them? Make them out of metal, like steel? And then what, cut each groove? Probably not (although that's exactly how the original lacquer disks were made). A moldable plastic sounds like a good idea. And that's how the majority of disks were (and still are) made: take a hot lump of vinyl, about the size and shape of a hockey puck, and press it between two hot disks of metal into which are carefully machined (ie, cut) grooves. Use enough pressure and the vinyl will replicate nearly every nuance of the mold. Although you can do this with a hard plastic, plastics are all pretty soft, and hard plastics have a regrettable tendency to break easily because they're brittle (like the old 78 RPM disks).
Now, you can argue that perhaps a less expensive material could be used instead of diamond for the needle, and was for a long time (eg, garnet), but the materials cost of industrial diamonds that weigh a few micrograms is next to nothing. The expense is in the shaping (playback needles aren't just pointed cones, at least good ones weren't) since that requires highly specialized equipment and skilled labor.
So, yes, it is brilliant to use diamond and vinyl. Did you ever see black dust or ribbon coming off of a record from the needle -- at least for one that was in proper alignment and not being dragged crosswise? I never did. And I still have my very playable record collection. The wear in records was not from removal of material, as with many wear mechanisms, but in gradual reshaping of the groove as the needle passed through. Thus the progress over time to lighter and lighter contact pressures and lighter and lighter cantilevers, with lighter and lighter moving masses -- eg, the moving magnet approach.
Put my fist through my alarm clock with its ding-dong death inside my ear. - The Blackjacks.