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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)

#32

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

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.

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

#33
post #29
post #9

Earlier quoted context omitted.

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…

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.

Yes that's also very important - the inverted EQ applied by the phono preamp pushes the noise floor way down in the treble, while raising it in the bass. In my opinion, this is probably why vinyl can never compete with digital when it comes to clean-sounding bass, but can generally have equally detailed treble when cared for well and played on a good turntable

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

#34

Earlier quoted context omitted.

This is part of what people hear when they say "vinyl sounds better."

That doesn't make any sense. RIAA EQ is a serialization format, that is then decoded by your audio equipment. That's what the phono jack is for on a receiver, pre-amp, etc. What people "hear" regarding LPs is generally their biases + their particular analog setup. My setup is going to sound totally different than yours, regardless if it's from a CD or an LP. There are some cases where an LP had a better -master- than…

I found out when digitizing vinyl that LP's before 1977, when digital mixing and mastering was not the norm that there is more data in the frequencies between 20 and 50kHz. I do my recording standard at 192kHz and analogue LP's often reach 48kHz of data while digital mastered ones do only 22kHz. After that date often the frequency is cutoff at 20-22kHz, probably to save memory room. Only after 2000-2010 there is enough memory to record at insane sample rates and bits per sample. Most awful are cds having only 16 bits and 41kHz sample rate, by modern standards really poor.

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

#36

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.

Also capture the audio sample from the same record alongside the video. Repeat with lots of records. Train a model to predict the audio from the video. Voila! Play records with just the camera “stylus”...

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

#37
post #34

Earlier quoted context omitted.

That doesn't make any sense. RIAA EQ is a serialization format, that is then decoded by your audio equipment. That's what the phono jack is for on a receiver, pre-amp, etc. What people "hear" regarding LPs is generally their biases + their particular analog setup. My setup is going to sound totally different than yours, regardless if it's from a CD or an LP. There are some cases where an LP had a better -master- than…

I found out when digitizing vinyl that LP's before 1977, when digital mixing and mastering was not the norm that there is more data in the frequencies between 20 and 50kHz. I do my recording standard at 192kHz and analogue LP's often reach 48kHz of data while digital mastered ones do only 22kHz. After that date often the frequency is cutoff at 20-22kHz, probably to save memory room. Only after 2000-2010 there is enou…

"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 with that audio and warrants the extra headroom, before mixing back to 44.1kHz/16bit for distribution. [1]

The only thing that higher bits/sampling rates do for a listener is waste CD and drive space, so it is odd to lament 44.1kHz/16bit as being "really poor". Even if your speaker setup can actually output extremely high frequencies, only your dog will be able to hear it...

[0]: https://en.wikipedia.org/wiki/Nyquist%E2%80%93Shannon_sampli...

[1] https://web.archive.org/web/20181109203430/https://people.xi...

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

#39

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

Amazing. Thank you. I immediately saved this, bookmarked it, and shared it with half a dozen people.

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

#40
post #9

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…

Slide/negative scanners use multiple passes and depth perception to cleanly ignore dust on film. I'm surprised that this wasn't part of ELP's spec to the engineers. A giant fail if they can't even remove this noise in post-processing.
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