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Conference cookie::notes$archive:cd_v1

Title:Welcome to the CD Notes Conference
Notice:Welcome to COOKIE
Moderator:COOKIE::ROLLOW
Created:Mon Feb 17 1986
Last Modified:Fri Mar 03 1989
Last Successful Update:Fri Jun 06 1997
Number of topics:1517
Total number of notes:13349

783.0. "Reconstructing copygaurded mangles?" by ISTG::YERAZUNIS (VAXstation Repo Man) Tue Jun 09 1987 17:19

    I was looking at how the cbs copygaurd scheme seems to work, and
    I think I see an easy way to both restore the missing sound (being
    a violin concerto fan this is important to me) and defeat the CBS
    system (not liking CBS recording execs too much, either).
    	
    The CBS system works by inserting a 3835 Hz notch filter (90 dB
    deep) and switching between the filter output and the unfiltered
    input at 400 Hz.  The notch is 125 Hz wide.
    	
    Hypothesis: the CBS copygaurd chip works by looking at the envelope
    of energy in this band, and seeing if it sees a 400 Hz tone in the
    envelope.  
    	
    Why this is bad: the 3835 Hz note is A# below the high C on a piano.
    This note will have lots of phasing effects. Every other A# note
    will have phasing effects (and a 400 Hz intermodulation) in the
    harmonics.
    	
    Solution: Build a phase-lock loop to lock to the strongest signal
    in the 3835 +- band.  (cost- $2).  Use the LOCK signal from this
    phase-lock loop to turn OFF the output of part B of this circuit.
    Build a second PLL, which slaves to the first, and has a sample-and
    hold in the VCO feedback (controlled by the LOCK signal of part
    A).  
    	
    Now, when the filter in the CBS music-mangler is out-of-loop, the
    first PLL locks to the to-be-mangled note, and signals that the
    music is OK, no additives needed.  The second PLL locks to the first,
    and outputs the note.
    	
    When the mangler engages, the first PLL loses lock, and kills the
    VCO feedback in the second PLL.  The second PLL continues to output
    the saved frequency.  1/400 second later, the note comes back, and
    both VCO's re-lock....
    	
    Now, to keep the saved note amplitude right- use the signal-strength
    output of the #1 PLL into a second sample-and-hold.  Put this into
    an op-amp as the reference input.  The fed-back input is signal
    strength of the #2 VCO controlled by a CMOS switch acting as a 
    voltage-controlled resistor.  
    	
    So, now we have a duplicate of the missing note, with correct
    amplitude. We use the LOCK signal to gate this into the output signal
    as needed, to reconstruct the mangling.
    	
    	Total cost - 2 PLL's ($4)
                     1 opamp  $1
                     1 quad CMOS switch $.79
                     random stuff - $5.00
    	
    	Final cost - $10.79
    	
    Comments?  Will this work?  Will it sound OK?  Will it get rid of
    the 400 Hz IMD product?  Will it defeat the copygaurd system?
    
T.RTitleUserPersonal
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783.1COVERT::COVERTJohn R. CovertTue Jun 09 1987 23:218
Is CBS already releasing copyguarded disks?

I had already decided to avoid most CBS disks on quality grounds; this could
clinch it.

If no one buys their disks, they won't have to worry about anyone copying them!

/john
783.2KRAKAR::WARWICKDNA puts life into your networkWed Jun 10 1987 08:235
    
    Do CBS claim that we won't be able to hear this tampering with the
    signal if the CD is played on a standard CD player ?
    
    Trev
783.3the notesfile you save, may be this one!VLNVAX::KARLSONOnly 198 shopping days until Xmas!Wed Jun 10 1987 08:295
    
    Please refrain from posting notes that deal with such topics as
    "defeating copyguards".
    
    							-rjk
783.4QUARK::LIONELWe all live in a yellow subroutineWed Jun 10 1987 11:4411
    I'd agree that we should not discuss means of illegally defeating
    protection mechanisms, but the fact is that there is no law against
    building circuits that may or may not have some effect on a yet-to-
    be-released audio copy protection scheme.  There ARE laws against
    video descrambling.  In my view there's nothing wrong with talking
    about CBS's scheme and ways to defeat it.  If Congress ever
    does pass a law on this topic, unlikely, then maybe we'll have to
    hide a few notes.
    
    
   				Steve
783.5VLNVAX::KARLSONOnly 198 shopping days until Xmas!Wed Jun 10 1987 11:466
    
    RE: .-1
    
    	And with that stated, he felt better and set the notes/UNHIDDEN.
    
    							-rjk
783.6WONDER::OUELLETTEOooh, Crumbs!Wed Jun 10 1987 16:2627
RE: What copy guard sounds like...

About a week ago on the news there was a story DAT.  They talked
about the copying issues, as well as comparing the sound of copy
guarded music vs. normal stuff.  The difference was quite
noticeable even through my [insert derogatory adjective] black and
white TV.  The former sounding like spring water and the latter
like pond scum.

RE: Using VCO's to reconstruct the audio signal...

I think your scheme might fool a copy guard chip, but I doubt
that it would sound any better.  If your music signal has more
than one frequency in the notch filter range, you'd not recover
the entire contents of that range.

Now if you discreetly sampled the signal when present.
[Multiple samples during each phase would be necessary.]  And
then send the samples through some hairy digital signal
processing hardware.  And finally reinserted the signal back
into the music in phase, and without too much harmonic
distortion, it might sound OK.

But then I was never a signals and systems god, so I could be
wrong,

R.
783.7If it's noticeable through a tin can...EXODUS::LEVYIs reality an implementation?Wed Jun 10 1987 18:1112
    re: -.1
    
    >about the copying issues, as well as comparing the sound of copy
    >guarded music vs. normal stuff.  The difference was quite noticeable
    >even through my [insert derogatory adjective] black and white TV.  The
    >former sounding like spring water and the latter like pond scum. 
     
    If one can hear audible differences using lowfi TV speakers, it
    seems ludicrous that this scheme would be accepted by the music
    industry, let alone the music-buying public...
    
    Jon
783.8You can HEAR the differenceFROST::EDSONDFri Jun 12 1987 14:258
    I saw the same news cast.  I'm not a golden ears person, and I noticed
    quite a difference between the before and after copyguard sound!
    
    I don't mind them (RIAA) being concerned with piracy.  I DO take
    offense to them destroying the MASTER (my CD).  Leave it to CBS
    to destroy their music, and others, beyond what they already do!
    
    Don
783.9I don't care any more.ISTG::YERAZUNISVAXstation Repo ManMon Jun 15 1987 14:329
    Well, over the weekend, I went out and bought all of the CBS releases
    I ever intend to purchase... ever.  All two of them.  
    	
    Let's just hope that Polydor, London, and Deutsche Gramophon stick
    by their guns, and refuse to mangle their own music.
    	
    A question to the ears that have actually heard copygaurded music:
    can you describe the distortion? 
    
783.10tiny bubblesIMORTL::OUELLETTEOooh, Crumbs!Mon Jun 15 1987 14:438
It sounds kind of like the music is being played underwater and
you hear the sound coming through in bubbles.  The piece that
was played did include a fair amount of information in the
notched area of the spectrum -- it was some kind of music with
bells and violins (I think) -- but I think that most anything
would sound pretty muddled.

R.
783.11COVERT::COVERTJohn R. CovertMon Jun 15 1987 23:3480
Senate Bill S. 506, the "Digital Audio Recorder Act of 1987" was introduced on
5 February 1987 by Senator Gore (D-Tenn.) for himself and for Senators Wilson,
Cranston, Danforth, and Kerry.

An interesting part of the introduction given by Mr. Gore was the 3-year sunset
provision, justified by the following: "I believe that this sunset provision is
necessary because the solution to the digital home taping problem, as well as
for the home taping issue in general, must be ultimately developed under the
copyright laws."  This clearly states that current copyright law does not forbid
private taping, and supports what Charles D. Ferris (former chairman of the FCC)
stated last December in an article on DAT in the New York Times: "If anyone
makes a copy and sells it, that's piracy, but if you do it for you personal use,
that's a right you obtain when you purchase a disk."  This legislation would
remove that right where DAT is concerned and would portend future legislation
further restricting that right for all media.

S. 506:  Be it enacted by the Senate and House of Representatives of the United
States of America in Congress assembled,

				Short Title
Section 1. This Act may be cited as the "Digital Audio Recorder Act of 1987".
				Definitions
Sec. 2. As used in this Act, the following terms and their variant forms have
the following meanings:
(1) "Commerce" means commerce among the several States of the United States or
with foreign nations, or in any territory or possession of the United States or
in the District of Columbia, or among the territories or possesions or between
any territory, possession, State, foreign nation, or between the District of
Columbia and any State, territory, possession, or foreign nation.
(2) A "copy-code scanner" is an electronic circuit or comparable system of
circuitry (A) wich is built into the recording mechanism of an audio recording
device; (B) which, if removed, bypassed, or deactivated, would render inoper-
ative the recording capability of the audio recording device; (C) which contin-
ually detects, within the audio frequency range of 3,500 to 4,100 hertz, a notch
in an encoded phonorecord; and (D) which upon detecting a notch, prevents the
audio recording device from recording the sounds embodied in the encoded phono-
record by causing the recording mechanism of the device to stop recording for
at least 25 seconds.
(3) A "digital audio recording device" is any machine or device, now known, or
hereafter developed, which can be used for making audio recordings in a digital
format.  The term "digital audio recording device" includes any machine or
device which incorporates a digital audio recording device as a part thereof.
(4) An "encoded phonorecord" is a phonorecord which has a notch with the audio
freqency range of 3,700 to 3,900 hertz.
(5) A "notch" is an absence of sound resulting from the removal of sound at a
certain frequency.
(6) A "person" includes any individual, corporation, company, association, firm,
partnership, society, joint stock company, or any other entity.
(7) A "phonorecord" is a material object in which sounds, other than those
accompanying a motion picture or other audiovisual work, are fixed by any method
now known or later developed, and from which the sounds can be perceived,
reproduced, or otherwise communicated, either directly or with the aid of a
machine or device.  The term "phonorecord" includes the material object in
which the sounds are first fixed.
			Digital Audio Recording Devices
Sec. 3. (a) No person shall manufacture, assemble, or offer for sale, resale,
lease, or distribution in commerce (1) any digital audio recording device which
does not contain a copy-code scanner; or (2) any device, product, or service,
the primary purpose or effect of which is to bypass, remove, or deactivate a
copy-code scanner.  Provided, That any patent, technical know-how, or proprie-
tary rights necessary for manufacturing a copy-code scanner have been made
available by means of a royalty-free license.
  (b) No person shall bypass, remove, or deactivate a copy-code scanner.
				Remedies
Sec. 4. (a) Any person aggrieved by any violation of section 3, or any approp-
riate officer or agency of the United States, may bring a civil action in any
appropriate United States district court.
...
(b) An aggrieved party shall be entitled to recover damagers...
  (1) ... actual damages ...
  (2) ... statutory damages in an amount of not less than $1,000 nor more than
	(A) $10 multiplied by the number of devices ... or
	(B) two times the cumulative retail value ...
(c) ... impounding ...
(d) ... destruction ...
(e) Any person who knowingly, willfully, and for purposes of direct or indirect
commercial advantage or private financial gain violates section 3(a) shall be
subject to criminal prosecution and may be fined, or imprisoned for not more
than two years, or both.  Fines shall be computed at five times the retail value
of the devices, products, or services involved or $50,000, whichever is greater.
783.12AKOV75::BOYAJIANIn the d|i|g|i|t|a|l moodTue Jun 16 1987 01:5118
    re:.6
    
    "...as well as comparing the sound of copy guarded music vs.
    normal stuff. The difference was quite noticible... The former
    sounding like spring water and the latter like pond scum."
    
    So, if the copyguarded music sounds like spring water and the
    normal stuff like pond scum, then what's everyone complaining
    about? :-)
    
    You say that the copyguarded stuff sounds muddy. Maybe this is
    what the problem was on CBS' remastered versions of some jazz
    classics they reissued.
    
    I guess I'm going to have to give up on CBS. Just as well, I
    have too many other CD's to get anyways.
    
    --- jerry
783.13COVERT::COVERTJohn R. CovertTue Jun 16 1987 02:0910
>    I guess I'm going to have to give up on CBS. Just as well, I
>    have too many other CD's to get anyways.

I doubt that if this catches on that CBS will be the only company doing it.

And forget about imports:  one of the proposals before the EC Parliament
would call for two-tier pricing in Europe:  one price for copy-guarded
releases, a higher price for copyable versions of the same material.

/john
783.14On the Label?PARSEC::PESENTIJPTue Jun 16 1987 08:075
Does anyone know if the copyguarded discs will have a label indicating the 
fact?

						     
							- JP
783.15IMORTL::OUELLETTEOooh, Crumbs!Tue Jun 16 1987 10:453
re: .12

Oops, a braino!
783.16REGENT::SCHMIEDERTue Jun 16 1987 16:4831
I haven't heard any CBS CD's yet, but I DID purchase three digitally 
remastered albums.  They were HORRIBLE!  The horns are barely audible, cymbals 
are clipped so that the music has no feeling of rhythmic drive, and there's an 
incredible amount of distortion in the upper frequencies.

I did some blindfold tests with friends using these and my pre-digital 
versions.  No one even thought the digital versions sounded like music.  Since 
these were the first digitally remastered LP's I had purchased, I lost faith 
in digital technology completely, until I read the article in this month's 
Music & Sound Output.  Now I know exactly what each company is up to, and 
which companies to avoid.

So, I'm very confused.  The law seems to indicate that the copyguard applies 
to CD's AND LP's.  So, the fact that my CBS remasters are vinyl probably isn't 
significant to this discussion.

If copyguard is one of the main reasons I'm hunting down the remaining 
originals of vintage CBS jazz releases I do not already own (and, fortunately, 
there are few of them not already in my possession), then I'd like to know HOW 
you can tell whether an LP or CD is copyguarded or not.

As it is, I have practically gone broke this year in a panic state to buy all 
the records I'll ever want before it's no longer possible to buy them (mostly 
used, except for the jazz category).

I'm not putting down CD's.  My gripe has never been with CD's or the better 
players, but with idiot engineers.  There seems to be an abundance of them 
lately, especially at CBS (always a prime training ground for boobs).


				Mark
783.17Using it already?DSSDEV::STRANGEBeing for the benefit of Mr. KiteTue Jun 16 1987 17:006
    I am confused.  Is it the case that CBS is already using copyguard?
    I thought this was still to be decided.  If they are using it, are
    they the only company?
    
    	Steve
    
783.18Anybody remember Quad?LYMPH::DICKSONNetwork Design toolsTue Jun 16 1987 18:015
Drat.  Philip Glass only records on CBS.

Looks like CDs may be a flash in the pan.  Demand will drop considerably if 
this goes into effect.  Killed by tin-ear legislators and greedy record 
companies.
783.19WRITE LETTERS NOW BEFORE ITS TOO LATEWCSM::PURMALBig is more than small is lessTue Jun 16 1987 18:5410
        Instead of keeping your opinions here write some letters and
    send them to the people who matter.  Write to your senators and
    congressmen.  Write CBS and tell them that you will not buy CD's
    that have been copyguarded.  Write to the artists who record for
    CBS and tell them that you will not be buying their CD's if CBS
    goes ahead with their copyguarding plans.
    
        I don't know how much effect a letter has on recording companies
    but television companies have responded in the past to letter writing
    campaigns.
783.20Any names & addresses for us semi-ambitious folks?PARSEC::PESENTIJPTue Jun 16 1987 19:471
783.21COVERT::COVERTJohn R. CovertTue Jun 16 1987 21:1955
Columbia Records / CBS Inc. / 51 W. 52 St. / NYNY.

All Senators can be reached at "Senate Office Buildings/Washington, D.C. 20510"

You should write to your own senator, no matter where you live.  People who live
in states with senators on the committees currently dealing with this bill are
the ones who are most likely to be able to help.  But write anyway.

The Bill was assigned to the Committee on Commerce, Science, and Transportation.
The responsible subcommittee is the Consumer Subcommittee -- the bill was intro-
duced by its chairman!  It has been referred for advice to the Committee on the
Judiciary, where the responsible subcommittee is Patents, Copyrights, and Trade-
marks.  But it's owned by commerce -- the idea is to try to get this through as
a trade bill since this sort of copyright legislation has been rejected in the
past.  Judiciary referred it to the National Bureau of Standards for technical
evaluation.  Commerce could still bring it out to the floor, no matter what NBS
says.

The members of the Consumer Subcommittee are:
	Gore, Tenn.		Kasten, Wisc.
	Ford, Ky.		McCain, Ariz.
	Breaux, La.

The members of the Patents, Copyright, and Trademarks Committee are:
	DeConcini, Ariz.	Simpson, Wyo.
	Kennedy, Mass.		Grassley, Iowa
	Leahy, Vt.		Hatch, Utah
	Heflin, Ala.

The bill was introduced by:
	Gore, Tenn.		Danforth, Mo.
	Wilson, Calif.		Kerry, Mass.
	Cranston, Calif.

The members of the Committee on Commerce, Sciences, & Transportation are:
	Hollings, S.C.		Inouye, Hawaii		Ford, Ky.
	Riegle, Mich.		Exon, Neb.		Gore, Tenn.
	Rockefeller, W.Va.	Bentsen, Texas		Kerry, Mass.
	Breaux, La.		Adams, Wash.		Danforth, Mo.
	Packwood, Oregon	Kassebaum, Kansas	Pressler, S.D.
	Stevens, Alaska		Kasten, Wisc.		Trible, Va.
	Wilson, Calif.		McCain, Ariz.
    Majority Chief Counsel & Staff Director:  Ralph B. Everett, SR-254
    Minority Chief of Staff: W. Allen Moore, SD-554

The members of the Committee on the Judiciary are:
	Biden, Del.		Kennedy, Mass.		Byrd, W.Va.
	Metzenbaum, Ohio	DeConcini, Ariz.	Leahy, Vt.
	Heflin, Ala.		Simon, Ill.		Thurmond, S.C.
	Simpson, Wyo.		Grassley, Iowa		Hatch, Utah
	Specter, Pa.		Humphrey, N.H.
    Majority Chief Counsel: Mark Gitenstein, SD-224
    Minority Chief Counsel & Staff Director: Dennis W. Shedd, SD-148

/john
783.22Look it upLYMPH::DICKSONNetwork Design toolsWed Jun 17 1987 10:256
Also you can look in your local telephone book, in the white pages, under
"United States Government, Congress" and find the number and address of
your particular senator or representative's local office. 

For example, I notice that rep Judd Gregg (NH) has an office in Nashua, and
Sen Gordon Humphrey (NH) has a toll-free number into his Concord office. 
783.23Toll Free InformationUSRCV1::THOMPSONPPaul ThompsonWed Jun 17 1987 10:444
    There is a number you can call for more information on this.  It
    is 800-282-TAPE.  So far I've got nothing but an answering machine
    in my attempts to call.
    
783.24COVERT::COVERTJohn R. CovertWed Jun 17 1987 13:1315
The folks at 800 282-TAPE are located in Washington, D.C., so you should call
during office hours there.

Two organizations run out of the same office:

	Audio Recording Rights Association
	Home Recording Rights Association

The organizations are Audio and Video, respectively.  Some of the information I
have posted was obtained by calling them, other info by going to the local
libraries.  They've also pointed me at a House bill, very similar to the
Senate bill, which I intend to look up the next time I get to the Lexington
library (Acton doesn't get the Congressional Record).

/john
783.25Give'um a callSRFSUP::GOLDSMITHI salute Kernel Mode!Wed Jun 17 1987 13:2110
    
    re .-1:
    
    I just talked to a rather nice sounding woman at the "Recording
    Rights Coalition" (the 800 number). And see is sending me an information
    pack. She says as of now, no one is using the encoding, however,
    CBS has said they will start this summer.
    
    							--- Neal
    
783.26QUARK::LIONELWe all live in a yellow subroutineWed Jun 17 1987 22:404
    I just received the July High Fidelity that has a long article
    on "Copy Code", and suggests ways around it.  Very interesting
    reading.
    				Steve
783.27CBS -- famous for: SQ quadrophonic !BOXTOP::QUIMBYWed Jun 24 1987 10:5811
    Re:  .18  ("anybody remember quad?")
    
    Just skimmed the High Fidelity article about the copyguard system.
    
    Same kind of tortured signal-processing manipulation CBS tried
    to foist off on the world with SQ quad.  They must have dragged
    the engineer who invented SQ out of retirement -- I picture this
    person as being deaf and sublimating through circuit diagrams and
    theoretical response curves.
    
    dq