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

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

#51

Post by 3dee »

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 turntables need 'clipping' filters. Dust will create all kinds of noise you don't want to hear.

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

#52

Post by Koshkin »

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 bits (say, of a zip file) as dots, and then you could use a scanner to read the file back!

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

#53

Post by genewitch »

andrewzah wrote: post #46
bluGill wrote: post #43

Earlier quoted context omitted.

There are one of several things. 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. Vinyl is sold to people who care about sound, in their living rooms so they get better mastering. Digital is for people out and about, in your car you need compression even though it destroyes the music you can't even hear 3/4ths of the sound without it.…

"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 being biased by the overall quality of the sound damping and accoustics of the room.

And objectively, i know that CDs are "pure". I also really can't hear the difference between a mastered 96khz 24 bit raw audio file, FLAC, or ~300ABR Mp3. And before it's mentioned, i have much better hearing than anyone i know, even if i have lost the ability to distinguish words when someone talks to me off-axis. the other night i heard my nearest neighbor playing music, and no one else could, here. Neighbor is like 1/4 mile away, from inside their house to inside my house. I brought my tascam to the back door and recorded[0]. Sure enough, the recording has a high noise floor but you can see the bass hits.

I still prefer live electronica shows where the DJ has pennies taped to their stylus, but i watch DJs on twitch using laptops and DJ-I digital turntables. All this to say, i've never made fun of someone spending thousands on pre-amps, amps, speakers, decks, whatever. If someone likes the way a Marantz sounds, or a Pioneer, or JBL or klipsch speakers - it doesn't affect me at all.

We're not using skippy CD players and realaudio/56kbit mp3s anymore!

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

#54

Post by TylerE »

dylan604 wrote: post #44
TylerE wrote: post #29

Earlier quoted context omitted.

Noise is also a big part of the RIAA curve. Almost all the noise on a record is high frequency...so by applying a strong treble rolloff most of it just disappears.

Sounds like DolbyNR for cassettes. What high hats?

It's a lot more clever than that.

Because the music has the exact inverse transform applied it before it's cut to the master, you don't lose any signal, just noise.

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

#55

Post by LeoPanthera »

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…

> it works great.

It does not work great.

The problem is dirt, which sounds like a minor issue, but it renders the concept almost completely useless.

A stylus pushes dirt out of the groove as the record turns. A laser cannot do so, and it's virtually impossible to fully clean a record.

The only remaining advantage is that a laser turntable does not wear out the disc, and it's an incredibly minor advantage, compared to simply playing a record once on a traditional player, and recording the output.

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

#56

Post by m463 »

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…

you would still need to use a de-linted discwasher with de-ionized water:

https://archive.org/details/stereo-review-presents-stereo-bu...

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

#57

Post by shagie »

andrewzah wrote: post #46
bluGill wrote: post #43

Earlier quoted context omitted.

There are one of several things. 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. Vinyl is sold to people who care about sound, in their living rooms so they get better mastering. Digital is for people out and about, in your car you need compression even though it destroyes the music you can't even hear 3/4ths of the sound without it.…

"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…

> Why would we have gone for inferior distribution mediums?

Higher data density, easier to manufacture, portable.

While we often phrase it as "vinyl vs CD" it was more a "tape vs CD". And CD is arguably the better technology there.

In https://www.soundguys.com/vinyl-better-than-streaming-20654/ - there is a chart of "Music sales by media" and you will see that CD - it replaced cassette tapes. Another view of similar data - https://blogs.sas.com/content/graphicallyspeaking/2019/11/11...

And even with that, "the best technology wins" isn't always the case. One could make a reasonable argument laser disks were better than video tapes and that Beta was better than VHS.

There are forces beyond the pure technology comparison at work in market dominance.

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

#58

Post by carlmr »

Yaa101 wrote: post #49
andrewzah wrote: post #37

Earlier quoted context omitted.

"Most awful are cds having only 16 bits and 41kHz sample rate, by modern standards really poor." 44.1kHz is all that one needs for -perfect fidelity-, given that humans cannot hear higher than ~20kHz. See: Nyquist-Shannon Sampling Theorem. [0] 16 bits of quantization gives a Signal to Noise Ratio (SNR) of 96dB, and noise dithering increases that [1]. More bits are not necessary unless one is doing music production wi…

I am doing production with these recordings, tools are more precise at higher bit and sample rates. Also quality of listening equipment is a factor as hearing is not a flat frequency response, things as ambiance and resonance play a role, music is not a single frequency tone but a combination of complicated frequency additions, subtractions, multiplications and divisions. So more frequency room can produce nicer high…

>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 headphones and a dedicated player with a good DAC chip playing a 96kHz song on a good quality headphones.

When everything you compare to is better quality then of course it sounds better. But it's not due to the 96kHz vs 44.1kHz. Nyquist-Shannon is mathematical reality.

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.

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

#59

Post by m463 »

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…

I wonder if they could do what film scanners do - they use an IR channel.

EDIT: and as soon as I submitted I realize film scanners scan for light and maybe use the IR channel for physical scanning. with a record everything is physical.

or maybe the IR channel focuses on a different plane? could they use different wavelengths for distance sensing/separation?

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

#60

Post by summm »

Yaa101 wrote: post #49
andrewzah wrote: post #37

Earlier quoted context omitted.

"Most awful are cds having only 16 bits and 41kHz sample rate, by modern standards really poor." 44.1kHz is all that one needs for -perfect fidelity-, given that humans cannot hear higher than ~20kHz. See: Nyquist-Shannon Sampling Theorem. [0] 16 bits of quantization gives a Signal to Noise Ratio (SNR) of 96dB, and noise dithering increases that [1]. More bits are not necessary unless one is doing music production wi…

I am doing production with these recordings, tools are more precise at higher bit and sample rates. Also quality of listening equipment is a factor as hearing is not a flat frequency response, things as ambiance and resonance play a role, music is not a single frequency tone but a combination of complicated frequency additions, subtractions, multiplications and divisions. So more frequency room can produce nicer high…

44.1/16 is enough for distribution. This is not simplistic. It simply can reproduce waveforms up to the nyquist frequency perfectly within a defined noise range. That's a mathematically proven fact. Of course you can botch that with bad listening equipment, but there's nothing a ridiculously oversampled signal would improve given the same listening equipment. You do speak about the studio processing right?
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