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Digital Needle: Ripping vinyl records with a scanner (2013)

cs.huji.ac.il

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Re: Digital Needle: Ripping vinyl records with a scanner (2013)

#81

Post by h2odragon »

magicalhippo wrote: post #77
pezezin wrote: post #68

Earlier quoted context omitted.

The only source I could find about humans hearing above 20 kHz is this paper reporting that some people could detect tones up to 28 kHz: https://asa.scitation.org/doi/10.1121/1.2761883 But that is for a pure tone under perfect laboratory conditions. Also, they report that the minimum hearing threshold at those frequencies was above 90 dB. So I don't think any human in this planet can actually hear anything above 20 k…

Couldn't beat[1] in the audible range occur from signals above 20kHz? [1]: https://en.wikipedia.org/wiki/Beat_(acoustics)

Yes, but that'll be captured in the CD range with the rest of that signal. My feeling is that few instruments, no music and little transducer equipment exists for that range (>20khz), and so few are aware of it without the intermediation of technical assistance, that theres no point in attempting to record or reproduce any of that. all it can do is add noise.

cf musopen. https://musopen.org/music/

They've got some lovely high bitrate and bandwidth recordings there, and what they've caught is room and audience noise. They'd have benefited from more mics and mixing and less "throw bits at it"

Re: Digital Needle: Ripping vinyl records with a scanner (2013)

#82

Post by karmanGO »

MrsPeaches wrote: post #11
Hfjfjdjfjceijfj wrote: post #8

Stero channels aren't encoded in the depth and radial axes. They're encoded in the same plane, but rotated 45 degrees, so a mono record player (depth only) plays a balanced sum of each channel. Edit: mono is radial only, not depth.

For anyone else who was intrigued by this, I found this helpful animation: https://www.vinylrecorder.com/stereo.html

That is a great explainer, simple and clear. Thanks for posting!

Re: Digital Needle: Ripping vinyl records with a scanner (2013)

#83

Post by stevage »

voldacar wrote: post #9
Scene_Cast2 wrote: post #3

I remember wondering whether a laser "needle" could work. IIRC the format has some funky EQ and other things to make a physical needle work better.

not cheap, but yeah it works great. https://www.elpj.com/ I actually got to hear one once. Extremely neutral and high-res, but the record has to be super clean because with the laser, you will hear every little speck of dust. Also it doesn't work with colored vinyl, iirc. edit: they use 5 different lasers to get the data out of the groove, go read the section on their site, it's actually really intricate and cool > t…

Surprised they can't just build in a little dust blower or a little brush or something to clean the surface just before it gets read.

Re: Digital Needle: Ripping vinyl records with a scanner (2013)

#84

Post by seba_dos1 »

genewitch wrote: post #53
andrewzah wrote: post #46

Earlier quoted context omitted.

"Vinyl is able to get a slightly better S/N ratio in perfect conditions." No. Compact Discs have an SNR of 96dB. Vinyl typically has an SNR of 60-70dB. The physics of these mediums aside, CDs are a newer technology... Why would we have gone for inferior distribution mediums? "Most likely, CDs just don't get mastered right. The music is compressed and so even though the format is better, the music is worse" Compressio…

>"When I worked in a studio, we would mix on $8k genelec monitors, some cheaper monitors, and also test the mix in our cars and on our phones." Yes! When i was producing an album a year, i'd write in monitor headphones, master on bookshelf monitors + a smallish subwoofer, then computer speakers, my car stereo, and a friend's street comp A car stereo. It's the only way to be sure that my ears in the "studio" weren't b…

> I also really can't hear the difference between a mastered 96khz 24 bit raw audio file, FLAC, or ~300ABR Mp3

An MP3 file at around 300kbps should be pretty much indistinguishable from FLAC for a human, so that's not surprising at all :)

The reason why I keep my music library as FLAC is not because it sounds better - it's because it's a perfect lossless copy of the original source that can be encoded to something lossy should a need arise. If I had to make 128kbps Opus files for some mobile use case, I'd rather do that from FLACs than MP3s. It also avoids double lossy compression when using things like A2DP.

Re: Digital Needle: Ripping vinyl records with a scanner (2013)

#85

Post by danmur »

ngcc_hk wrote: post #79
Fnoord wrote: post #67

Earlier quoted context omitted.

This website, as well as the one in the thread's URL, are exactly in the way as I learned the WWW was when I first started using it.

It fits its theme ... vinyl

Don't joke, we'll probably see web 4.0 distributed on vinyl soon enough. Just gotta get the assets down to less than 100mb.

Re: Digital Needle: Ripping vinyl records with a scanner (2013)

#86

Post by hulitu »

radomir_cernoch wrote: post #32
MrsPeaches wrote: post #11

Earlier quoted context omitted.

For anyone else who was intrigued by this, I found this helpful animation: https://www.vinylrecorder.com/stereo.html

Wow, the best example of teaching minimalism I know. Even though the website fails on so many levels, ;-) I still get the message in 15 seconds.

Maybe you are looking at the wrong one ? It loads instantly. I do not have to zoom to read the text. No node.js, cdn and other curses of "modern" web. The only annoying thing is that the guy went to great lenghts to get the audio only to convert it later to mp3. I guess there is no hope. ( it could have been worse - webm).

Re: Digital Needle: Ripping vinyl records with a scanner (2013)

#87

Post by ByThyGrace »

kurthr wrote: post #63
Dylovell wrote: post #38

The next thing will be electron microscope scans of of the instruments the artists used. I'm joking. I really want well digitized vinyl

You're joking, but based on the dynamic range (claimed by audiophiles) over a min length of ~160um (more on the outside less interior for 2kHz tone) and the peak motion ~37um per channel. PVC grains are typically 100s of um in size, but the monomers themselves are ~10nm. Note that with 120dB claimed dynamic range this would be 37nm of deflection (at 45deg or 25nm lateral) for full resolution. That is close (3x off) t…

Thanks for the informative explanation! If say an 12-inch LP is scanned at 250nm optical resolution, what output digital image resolution are we talking here (in pixels)?

Re: Digital Needle: Ripping vinyl records with a scanner (2013)

#88

Post by wwn_se »

Koshkin wrote: post #52

Now I'm dreaming about a program that would simply play a high-res photograph (scan) of a vinyl disk... This also reminds me of the idea to use paper for archival. This is based on two factors: that modern office paper is extremely durable (and is likely to outlast most of the other physical media out there), and that scanners are (and have been for years now) extremely high-resolution; so, you can simply print the b…

Interesting concept the biggest problem would probably be data density. Like how many papers would you need to to get about dvd size. Other than than the problems in getting a reader dvds is one of the best current long time solution.

Re: Digital Needle: Ripping vinyl records with a scanner (2013)

#89

Post by carlmr »

andrewzah wrote: post #70
carlmr wrote: post #58

Earlier quoted context omitted.

>It is simplistic to state that 44.1/16bit is enough, if that is the case then any combination of recording, amplifier and speaker would suffice. No, that doesn't follow. It just means that recording at those bit rates and sampling frequencies isn't the "bottleneck" for the sound in the system. >But there really is a difference between a phone with a music app playing a 16bit/44.1kHz song on a medium quality headphon…

"You have to compare the same high quality headphones, the amp with the same DAC, with the same recording, being played through a high quality filter bringing everything down to 44.1kHz/16bit." I agree. If there is a methodologically sound study showing that people can actually distinguish (>50%) between 44.1kHz/16bit and 192kHz/24bit on the same hardware [at exactly the same dB SPL], then I will be really surprised.…

I'd also be surprised. Even more so with grown-ups, most of them don't even hear >20kHz.

Re: Digital Needle: Ripping vinyl records with a scanner (2013)

#90

Post by IndySun »

3dee wrote: post #51
marcodiego wrote: post #2

Thinking about a simpler system... how about getting a camera on a turntable recording a video while the record turns. It would then be possible to track a line with an specified width in the video and turn the changes in a piece of this line it into a waveform.

I once thought about building this, but it's much harder than you think. The data has to be processed very quickly. I believe you should think in terms of 0.3m groove per second. If you put a camera above the groove you also need something like a stepper motor to control the arm. But I believe the biggest problem is dust. A needle will move small particles out of the way, but a camera does not. This is also why laser…

>The data has to be processed very quickly.

How about designing an arm that used more than one laser 'needle'?

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