11 ms·

Copy-protection for vinyl in the 1970s (2008)

124 points by wut42 5y ago

criddell 5y ago
> Either way, after a few plays it was destined to disappear due to regular wear and tear on the record's groove. Is vinyl really that delicate, or were record players in the 60's put more downforce on the needle?
- sumtechguy 5y ago
  One of the two surfaces is going to be 'softer'. Either the needle or the disc. Usually the disc lost out.
  - spijdar 5y ago
    On top of that, because of the way audio was recorded to vinyl, the higher frequency a sound was, there would be a disproportionate amount of wear/friction, I think. Either way, in this case the article is referring to the ultrasonic tone, and not to the records overall.
    - Someone 5y ago
      The explanation for that is simple: the groove is a 1:1 copy of the sound wave, so higher frequency sounds have smaller details in the groove. Those details wear away faster than larger ones. All mechanical record players have to pick a middle ground between picking up the sound wave and keeping the record surface pristine. To prevent wear, you want the needle to exert as little pressure as possible. That calls for a large needle that’s only lightly pressed onto the record surface. Unfortunately, that is exactly what you don’t need if you want to reliably pick up the signal. To prevent the needle from jumping from peak to peak in the groove due to its inertia, you want to press it onto the disk. Also, for the needle to pick up higher frequencies, it can’t be large (it has to be able to ‘fall’ into the grooves between the tops in the signal, and those are closer together for higher-frequency signals)
      - wheels 5y ago
        > the groove is a 1:1 copy of the sound wave False. There's an EQ curve that's applied to all records that rolls off the bass, which has to be re-added by the preamp. https://en.wikipedia.org/wiki/RIAA_equalization https://en.wikipedia.org/wiki/RIAA_equalization
  - rwmj 5y ago
    Which of course made a change from 78s where it was the needle that wore out on the hard shellac disc.
- wut42 5y ago
  I think it's both. Many players were not that gentle at the time (and, actually still is nowadays). Edit: I remembered that my dad frequently added a small coin on the top of the needle to avoid skips. So people weren't gentle with the vinyls and the needles either. It could also be that vinyl and RIAA encoding was made mostly for the range of the human ears, and such a high frequency would just wear way faster than the "normal" ones, but I'm speculating there. IIRC, the high frequencies are "higher" in the groove.
  - d_tr 5y ago
    Larger amplitudes and frequencies should give steeper slopes on the groove and therefore larger forces and friction, makes perfect sense. Isn't this why more heavily used vinyls sound a bit muffled?
    - lostgame 5y ago
      Well; that or, of course - general wear and tear or even dust in the grooves. Vinyl is very sensitive.
      - d_tr 5y ago
        Sure!
        TheOtherHobbes 5y ago
        In spite of the legend, the needle doesn't get hot enough to melt the groove. But repeated pressure does deform it slightly. And the HF detail in the groove is already so tiny that it doesn't take much to wear/deform it away. Vinyl really is the most ridiculous medium for music. I get the appeal of a large collectible object wrapped in stunning sleeve art, but in terms of audio quality it's the equivalent of a cheap plastic LOMO lens.
  - numpad0 5y ago
    I have heard a different explanation for coin trick, that you could add weights to match the heaviest cartridge/shell setup in your collection, so that any of it when installed exerts desired tracking force without having to balance the arm each time. I wonder whether having end mass at the shell helped or if both were cases of such first world problems.
amelius 5y ago
Side-question: what are people using today to copy-protect their software (other than running it as a SaaS)?
- unnouinceput 5y ago
  Half backed solutions that never work. If it can be read, it can be copied - it's that simple.
  - amelius 5y ago
    Ok, but some ARM CPUs are very cheap, so you could run part of your software on a small hardware box with tamper-proofing. The compiler could move the outer loops to the external CPU, and leave the inner loops to the main CPU which is faster. Of course you would have to think about how you move data around, but in principle why wouldn't this work?
    - unnouinceput 5y ago
      Cool, you do that then wage a million dollars it can't be copied then I'll come to collect the million. In the entire history of software there was absolutely zero copy protection for a determined person. Not just commercial one, but think of FBI/NSA/CIA level of protection, and yet they failed spectacularly when a determined individual wanted to steal the secrets. Hence my above "if it can be read, it can be copied".
    - h2odragon 5y ago
      Take a look at smart card authentication systems, for example those used in subscription TV services. The "smart card" is usually an 8051 type micro controller and does a little bit of cryptography to be the DRM. The battles between the companies and hackers in that scene were fascinating.
      - anthk 5y ago
        Those were hacked over and over.
rwmj 5y ago
Surely someone applied for a patent on this vinyl copy protection, so a patent search around the years, say, 1960-79 would be the first place to look.
- new299 5y ago
  Best I can find so far is this, which seems very similar to the method described, but is quite a bit later (1982): https://patentimages.storage.googleapis.com/3d/d5/b4/5beda2898d9cda/US4644422.pdf https://patentimages.storage.googleapis.com/3d/d5/b4/5beda28... > An anti-copy system which prevents copying of tapes and records and other source material by placing a degrade signal on an analog source signal to be recorded on a recording device. One embodiment of the system includes a pulse width modulation (PWM) circuit that generates a pulsed signal in a frequency range from near the upper end to well above the range of hearing. > However, attempts to make taped copies of the original recordings cause the degrade signal to beat against the bias oscillator frequency of the tape recording head, thereby creating harmonic signals that result in distortion and noticeable alteration of the reproduced source signal that are unpleasant and objectionable to the listener.
tyingq 5y ago
The warning label on "Almost Blue" mentioned in the article: https://img.discogs.com/UxLyf_K9PVFDQ2IXFSCcYd4dNZ8=/fit-in/600x407/filters:strip_icc():format(jpeg):mode_rgb():quality(90)/discogs-images/R-4378216-1440862019-6277.jpeg.jpg https://img.discogs.com/UxLyf_K9PVFDQ2IXFSCcYd4dNZ8=/fit-in/...
w0mbat 5y ago
Back in the 80s, CBS Records had a bee in their bonnet about making music untapeable and developed various technologies (analog and digital) which they branded CopyCode. There was a rumor that Sony bought CBS Records (now Sony Records) just to shut that nonsense down.
squeaky-clean 5y ago
Sort of related tangent, there were some attempts at copy-protection for VHS. Technology Connections has a good video [0] on "MacroVision" [1], which would mess with the vertical-blanking signal in a way that wasn't particularly noticeable on playback, but would mess with VHS recording. There was also apparently another method which was just a straight up lie, called KTC, that claimed it was coated with a chemical that would destroy any VHS recorder attempting to record it. Here's a screenshot of the pre-video bumper warning, alerting you to "STOP RECORDING NOW" [2]. Also any RedLetterMedia fans may remember this from the "dog sitting" video in Wheel of the Worst #7 (around 35:00 in). It sounds like a phony technology, and it is. It's just a lie intended to scare away anyone attempting to record the tape. [0] https://www.youtube.com/watch?v=-VqsU1VK3mU https://www.youtube.com/watch?v=-VqsU1VK3mU [1] https://en.wikipedia.org/wiki/Analog_Protection_System https://en.wikipedia.org/wiki/Analog_Protection_System [2] https://company-bumpers.fandom.com/wiki/K.T.C._Warning_Screen https://company-bumpers.fandom.com/wiki/K.T.C._Warning_Scree...
- Steve44 5y ago
  > which would mess with the vertical-blanking signal in a way that wasn't particularly noticeable on playback, but would mess with VHS recording On a related note, one of the copy protection systems I put on some Sinclair Spectrum cassette games involved changing the baud rate part way through loading. It was over 35 years ago so the details are hazy, but I had a custom "master maker" to play the audio[1] and at a specific byte count would change the frequency. The mastering and duplication machines coped with it fine and the loader was written to expect it, but it threw out most home tape to tape systems for reasons I can't exactly remember. [1] These were usually recorded directly from the Spectrum onto 2 inch reel to reel tapes in a studio, that was then used as the master at the duplicators.
- dylan604 5y ago
  Macrovision only worked on VCRs with the Automatic Gain Control (AGC) enabled. It was super easy to defeat by disabling the AGC, or if you had more sophisticated equipment like a time base corrector (TBC) or similar. These dubs will still have the Macrovision as is, but it won't affect the recording's video signal. Using a standards coverter NTSC->PAL for example would completely remove the macrovision from the dub.
omoikane 5y ago
I thought how they discouraged piracy back in the analog days was to make the physical packaging more desirable. This also happened later with games ("feelies").
throwawayboise 5y ago
In the late 1980s one of my business classes was a one-credit career placement class. Essentially they taught you how to interview and how to prepare a resume. The resume software came on a floppy disk and the professor (who had some kind of ownership stake in the software) warned the class that any attempt to copy the disk would render both the copy and the original unusable. It was bullshit of course, the disk could be copied and the software didn't even use any of the copy-preventing tricks that floppy-disk-based software often used in those days. But especially then, most students had little experience with computers and just believed it.
- cm2187 5y ago
  Or the Urine-indicator dye in swimming pools. A useful myth to spread in schools (which did in my school in the 90s).
  - audiometry 5y ago
    Yeah. Mid eighties I was warned that a purple cloud would erupt around me and even follow me if I tried to move away to escape blame.
Animats 5y ago
There have been copy-protected vinyl records.[1] Seeburg, the jukebox company, made some for their background music system. Recorded by Seeburg's own orchestra, to avoid copyright problems. Nonstandard groove width (.5 mil stylus), nonstandard hole diameter (2 inch), nonstandard speed (16 2/3 RPM), nonstandard outside diameter (9 inch), intended to be playable only on a special Seeburg record changer. They didn't bother to register copyright, back when copyright had to be registered. So some people have obtained the correct record stylus for these, made a 2 inch hole filler, set a modern turntable to the correct speed, and transcribed these records. If you like 1950s elevator music, it's available. [1] https://en.wikipedia.org/wiki/Seeburg_1000 https://en.wikipedia.org/wiki/Seeburg_1000
- PostThisTooFast 5y ago
  Thanks for that info. I have one of these records!
ncphil 5y ago
"Needles on domestic record players ignored the signal, often physically destroying the delicate groove in the vinyl that produced the spoiler." Ah. The good old days: when the forces of greed and corruption were constantly shooting themselves in the feet. Of course there were some regrettable casualties. Like DATs. Having started out in the vinyl era, I got about halfway through recording my 400+ album collection when I lost interest. Played with CDROMs a bit, but couldn't bothered to continue. I'm probably not typical, but for me the assault on DAT killed any desire to keep feeding the RIA machine.
deleted 5y ago
[deleted]
fortran77 5y ago
I'm not sure this story is true.
aaron695 5y ago
I think the article answers itself - > "Magic Alex" Mardas was not the revolutionary engineer he portrayed himself to be. In 1995, in an article about what became of The Beatle's hangers-on, The Independent described him as: > 'The Greek TV repairman, set up in Apple Electronics by the Beatles, who promised to build an artificial sun, a telephone you told who to call, wallpaper loudspeakers, a house which hovered supported by an invisible beam, and even a flying saucer. Not one invention was made, and the recording studio he built proved unusable and was demolished. Allen Klein fired him, and he has since disappeared.' https://en.wikipedia.org/wiki/Magic_Alex https://en.wikipedia.org/wiki/Magic_Alex
d13 5y ago
> a short snippet of nonsense noise Really??? Play it backwards :)

124 points by wut42 5y ago

> Either way, after a few plays it was destined to disappear due to regular wear and tear on the record's groove. Is vinyl really that delicate, or were record players in the 60's put more downforce on the needle?

sumtechguy 5y ago
One of the two surfaces is going to be 'softer'. Either the needle or the disc. Usually the disc lost out.
- spijdar 5y ago
  On top of that, because of the way audio was recorded to vinyl, the higher frequency a sound was, there would be a disproportionate amount of wear/friction, I think. Either way, in this case the article is referring to the ultrasonic tone, and not to the records overall.
  - Someone 5y ago
    The explanation for that is simple: the groove is a 1:1 copy of the sound wave, so higher frequency sounds have smaller details in the groove. Those details wear away faster than larger ones. All mechanical record players have to pick a middle ground between picking up the sound wave and keeping the record surface pristine. To prevent wear, you want the needle to exert as little pressure as possible. That calls for a large needle that’s only lightly pressed onto the record surface. Unfortunately, that is exactly what you don’t need if you want to reliably pick up the signal. To prevent the needle from jumping from peak to peak in the groove due to its inertia, you want to press it onto the disk. Also, for the needle to pick up higher frequencies, it can’t be large (it has to be able to ‘fall’ into the grooves between the tops in the signal, and those are closer together for higher-frequency signals)
    - wheels 5y ago
      > the groove is a 1:1 copy of the sound wave False. There's an EQ curve that's applied to all records that rolls off the bass, which has to be re-added by the preamp. https://en.wikipedia.org/wiki/RIAA_equalization https://en.wikipedia.org/wiki/RIAA_equalization
- rwmj 5y ago
  Which of course made a change from 78s where it was the needle that wore out on the hard shellac disc.
wut42 5y ago
I think it's both. Many players were not that gentle at the time (and, actually still is nowadays). Edit: I remembered that my dad frequently added a small coin on the top of the needle to avoid skips. So people weren't gentle with the vinyls and the needles either. It could also be that vinyl and RIAA encoding was made mostly for the range of the human ears, and such a high frequency would just wear way faster than the "normal" ones, but I'm speculating there. IIRC, the high frequencies are "higher" in the groove.
- d_tr 5y ago
  Larger amplitudes and frequencies should give steeper slopes on the groove and therefore larger forces and friction, makes perfect sense. Isn't this why more heavily used vinyls sound a bit muffled?
  - lostgame 5y ago
    Well; that or, of course - general wear and tear or even dust in the grooves. Vinyl is very sensitive.
    - d_tr 5y ago
      Sure!
      - TheOtherHobbes 5y ago
        In spite of the legend, the needle doesn't get hot enough to melt the groove. But repeated pressure does deform it slightly. And the HF detail in the groove is already so tiny that it doesn't take much to wear/deform it away. Vinyl really is the most ridiculous medium for music. I get the appeal of a large collectible object wrapped in stunning sleeve art, but in terms of audio quality it's the equivalent of a cheap plastic LOMO lens.
- numpad0 5y ago
  I have heard a different explanation for coin trick, that you could add weights to match the heaviest cartridge/shell setup in your collection, so that any of it when installed exerts desired tracking force without having to balance the arm each time. I wonder whether having end mass at the shell helped or if both were cases of such first world problems.

amelius 5y ago

Side-question: what are people using today to copy-protect their software (other than running it as a SaaS)?

unnouinceput 5y ago
Half backed solutions that never work. If it can be read, it can be copied - it's that simple.
- amelius 5y ago
  Ok, but some ARM CPUs are very cheap, so you could run part of your software on a small hardware box with tamper-proofing. The compiler could move the outer loops to the external CPU, and leave the inner loops to the main CPU which is faster. Of course you would have to think about how you move data around, but in principle why wouldn't this work?
  - unnouinceput 5y ago
    Cool, you do that then wage a million dollars it can't be copied then I'll come to collect the million. In the entire history of software there was absolutely zero copy protection for a determined person. Not just commercial one, but think of FBI/NSA/CIA level of protection, and yet they failed spectacularly when a determined individual wanted to steal the secrets. Hence my above "if it can be read, it can be copied".
  - h2odragon 5y ago
    Take a look at smart card authentication systems, for example those used in subscription TV services. The "smart card" is usually an 8051 type micro controller and does a little bit of cryptography to be the DRM. The battles between the companies and hackers in that scene were fascinating.
    - anthk 5y ago
      Those were hacked over and over.

rwmj 5y ago

Surely someone applied for a patent on this vinyl copy protection, so a patent search around the years, say, 1960-79 would be the first place to look.

new299 5y ago
Best I can find so far is this, which seems very similar to the method described, but is quite a bit later (1982): https://patentimages.storage.googleapis.com/3d/d5/b4/5beda2898d9cda/US4644422.pdf https://patentimages.storage.googleapis.com/3d/d5/b4/5beda28... > An anti-copy system which prevents copying of tapes and records and other source material by placing a degrade signal on an analog source signal to be recorded on a recording device. One embodiment of the system includes a pulse width modulation (PWM) circuit that generates a pulsed signal in a frequency range from near the upper end to well above the range of hearing. > However, attempts to make taped copies of the original recordings cause the degrade signal to beat against the bias oscillator frequency of the tape recording head, thereby creating harmonic signals that result in distortion and noticeable alteration of the reproduced source signal that are unpleasant and objectionable to the listener.

tyingq 5y ago

The warning label on "Almost Blue" mentioned in the article: https://img.discogs.com/UxLyf_K9PVFDQ2IXFSCcYd4dNZ8=/fit-in/600x407/filters:strip_icc():format(jpeg):mode_rgb():quality(90)/discogs-images/R-4378216-1440862019-6277.jpeg.jpg https://img.discogs.com/UxLyf_K9PVFDQ2IXFSCcYd4dNZ8=/fit-in/...

w0mbat 5y ago

Back in the 80s, CBS Records had a bee in their bonnet about making music untapeable and developed various technologies (analog and digital) which they branded CopyCode. There was a rumor that Sony bought CBS Records (now Sony Records) just to shut that nonsense down.

squeaky-clean 5y ago

Sort of related tangent, there were some attempts at copy-protection for VHS. Technology Connections has a good video [0] on "MacroVision" [1], which would mess with the vertical-blanking signal in a way that wasn't particularly noticeable on playback, but would mess with VHS recording. There was also apparently another method which was just a straight up lie, called KTC, that claimed it was coated with a chemical that would destroy any VHS recorder attempting to record it. Here's a screenshot of the pre-video bumper warning, alerting you to "STOP RECORDING NOW" [2]. Also any RedLetterMedia fans may remember this from the "dog sitting" video in Wheel of the Worst #7 (around 35:00 in). It sounds like a phony technology, and it is. It's just a lie intended to scare away anyone attempting to record the tape. [0] https://www.youtube.com/watch?v=-VqsU1VK3mU https://www.youtube.com/watch?v=-VqsU1VK3mU [1] https://en.wikipedia.org/wiki/Analog_Protection_System https://en.wikipedia.org/wiki/Analog_Protection_System [2] https://company-bumpers.fandom.com/wiki/K.T.C._Warning_Screen https://company-bumpers.fandom.com/wiki/K.T.C._Warning_Scree...

Steve44 5y ago
> which would mess with the vertical-blanking signal in a way that wasn't particularly noticeable on playback, but would mess with VHS recording On a related note, one of the copy protection systems I put on some Sinclair Spectrum cassette games involved changing the baud rate part way through loading. It was over 35 years ago so the details are hazy, but I had a custom "master maker" to play the audio[1] and at a specific byte count would change the frequency. The mastering and duplication machines coped with it fine and the loader was written to expect it, but it threw out most home tape to tape systems for reasons I can't exactly remember. [1] These were usually recorded directly from the Spectrum onto 2 inch reel to reel tapes in a studio, that was then used as the master at the duplicators.
dylan604 5y ago
Macrovision only worked on VCRs with the Automatic Gain Control (AGC) enabled. It was super easy to defeat by disabling the AGC, or if you had more sophisticated equipment like a time base corrector (TBC) or similar. These dubs will still have the Macrovision as is, but it won't affect the recording's video signal. Using a standards coverter NTSC->PAL for example would completely remove the macrovision from the dub.

omoikane 5y ago

I thought how they discouraged piracy back in the analog days was to make the physical packaging more desirable. This also happened later with games ("feelies").

throwawayboise 5y ago

In the late 1980s one of my business classes was a one-credit career placement class. Essentially they taught you how to interview and how to prepare a resume. The resume software came on a floppy disk and the professor (who had some kind of ownership stake in the software) warned the class that any attempt to copy the disk would render both the copy and the original unusable. It was bullshit of course, the disk could be copied and the software didn't even use any of the copy-preventing tricks that floppy-disk-based software often used in those days. But especially then, most students had little experience with computers and just believed it.

cm2187 5y ago
Or the Urine-indicator dye in swimming pools. A useful myth to spread in schools (which did in my school in the 90s).
- audiometry 5y ago
  Yeah. Mid eighties I was warned that a purple cloud would erupt around me and even follow me if I tried to move away to escape blame.

Animats 5y ago

There have been copy-protected vinyl records.[1] Seeburg, the jukebox company, made some for their background music system. Recorded by Seeburg's own orchestra, to avoid copyright problems. Nonstandard groove width (.5 mil stylus), nonstandard hole diameter (2 inch), nonstandard speed (16 2/3 RPM), nonstandard outside diameter (9 inch), intended to be playable only on a special Seeburg record changer. They didn't bother to register copyright, back when copyright had to be registered. So some people have obtained the correct record stylus for these, made a 2 inch hole filler, set a modern turntable to the correct speed, and transcribed these records. If you like 1950s elevator music, it's available. [1] https://en.wikipedia.org/wiki/Seeburg_1000 https://en.wikipedia.org/wiki/Seeburg_1000

PostThisTooFast 5y ago
Thanks for that info. I have one of these records!

ncphil 5y ago

"Needles on domestic record players ignored the signal, often physically destroying the delicate groove in the vinyl that produced the spoiler." Ah. The good old days: when the forces of greed and corruption were constantly shooting themselves in the feet. Of course there were some regrettable casualties. Like DATs. Having started out in the vinyl era, I got about halfway through recording my 400+ album collection when I lost interest. Played with CDROMs a bit, but couldn't bothered to continue. I'm probably not typical, but for me the assault on DAT killed any desire to keep feeding the RIA machine.

deleted 5y ago

[deleted]

fortran77 5y ago

I'm not sure this story is true.

aaron695 5y ago

I think the article answers itself - > "Magic Alex" Mardas was not the revolutionary engineer he portrayed himself to be. In 1995, in an article about what became of The Beatle's hangers-on, The Independent described him as: > 'The Greek TV repairman, set up in Apple Electronics by the Beatles, who promised to build an artificial sun, a telephone you told who to call, wallpaper loudspeakers, a house which hovered supported by an invisible beam, and even a flying saucer. Not one invention was made, and the recording studio he built proved unusable and was demolished. Allen Klein fired him, and he has since disappeared.' https://en.wikipedia.org/wiki/Magic_Alex https://en.wikipedia.org/wiki/Magic_Alex

d13 5y ago

> a short snippet of nonsense noise Really??? Play it backwards :)