Dear Mike, (1) Well, the CD format *is* well-documented, but a further consideration is that there are more than a billion "Red Book" players out there, whereas Edison made only about a million cylinder players. Yet it is simple to watch an Edison machine at work, and either create a new machine to do the same job, or modify a vintage machine to transfer the information electronically. This is only ordinary analogue engineering skill (although I agree the weakness could be in that last sentence!) The *documentation* survives. (2) Yes, this is beginning to happen, but the original patents (which expired here in the year 2000) mean the vast majority of CDs should indeed play, while the user-base of machinery means that the vast majority of audio CDs still need to be compatible with older players. Again, it's "software" which is the problem, mainly recipes for "surround-sound" encoding. (3) I'm afraid I don't know Sanyo's "V-cord" format, but the Elcassette contains quarter-inch tape which can be extracted from the cassette and wound onto a spool. It can then be played on any 4-track quarter-inch open-reel tape player. Likewise, another correspondent was bewailing the fate of "eight-track" cartridges. Personally, I have been studying these, because they often bear UNencoded quadraphonic recordings! They are not common on this side of the Atlantic, but I have now found twenty-one, and plan to move the tape from the cartridges onto open reels, and play them on an eight-track quarter-inch machine. From this, it should then be possible to fine-tune the SQ and QS encoding systems used for vinyl discs. Much of the above comes down to the fact that, for analogue recordings, there is much to be gained from having the same sound on two different formats. This is especially true if you accept the idea of getting back to what the original recording engineers would have wished. Peter Copeland -----Original Message----- From: Mike Richter [mailto:[log in to unmask]] Sent: 18 March 2003 16:14 To: [log in to unmask] Subject: Re: [ARSCLIST] Copyright and hard drives At 02:04 PM 3/18/2003 +0000, Copeland, Peter wrote: >Dear Joel, > Thanks for your posting. I've retired now, so I cannot speak for my >successor, but I see little need for an "open source" software decoder for >CDs. Any CD player with an SP-DIF output is capable of replaying everything >(including the track flags) complete with error-correction, so the audio and >the flags may be moved to any other audio hardware capable of the necessary >sampling-frequency and bit-resolution. (The AES digital connection-standard >will copy the audio, if necessary for very long physical distances; but it >does not include track flags. Our experiences with Betamax videotapes with >digital audio also showed it was relatively simple to retro-fit the machines >with SP-DIF outputs). I am out of my base of knowledge here, but would like to offer some questions with implied answers. 1. Is not the need for "open source" more for documentation so that the format can be reconstructed even after it has been abandoned by its owner? 2. As the patents on CD format expire, liberties are being taken with the color book standards. Is there not the risk that some 'protected' discs will deviate far enough to preclude easy movement to another medium or format? 3. The Betamax example is perhaps too weak since the hardware was well developed and in use for an extended period. Would the result have been similar for Sanyo's V-Cord video format or Sony's El-Cassette for audio? Mike [log in to unmask] http://www.mrichter.com/ ************************************************************************** Free exhibition at the British Library Galleries : Magic Pencil : Children's Book Illustration Today (to 31 March) original graphic work of 13 contemporary artists ************************************************************************* The information contained in this e-mail is confidential and may be legally privileged. It is intended for the addressee(s) only. If you are not the intended recipient, please delete this e-mail and notify the [log in to unmask] : The contents of this e-mail must not be disclosed or copied without the sender's consent. The statements and opinions expressed in this message are those of the author and do not necessarily reflect those of the British Library. The British Library does not take any responsibility for the views of the author. *************************************************************************