manheimer@nbs-amrf.UUCP (Ken Manheimer) (01/19/85)
I noticed in a recent issue of Stereo review (~ 2 or 3 issues back) a single page article about a prototype of a new audio recorder that had just been reviewed by the author. The interesting thing about it was the effective use of a standard computer floppy (I think 5 1/4", single side, double density) as the recording medium. With the benefit of what seemed to be an adaptive sampling technique, over an hour of high fidelity music could be recorded on a single disk. (The last I heard in this vein, a computer music wizard could fit 4 minutes of high fi per floppy; to play a synthesized version of Pachelbels canon that he recorded he had to gang two floppy disk "players" and go through a series of ~ 6 floppies! The sound was fine, as far as I could tell, though I was hearing it in a school auditorium...). The reviewer said that, while the sound may not be up to par with CD's, he felt it at least measured up to any vinyl (or was it any analog medium?) around. The price mentioned was somewhere near $1000 (1100?). Such a thing, if bona fide, has a lot going for it. Foremost is the opportunity to use it to to record as well as play back - the lack of which is CD's chief drawback for me, followed closely by their expense. On that count floppies would be a much a more economical medium once their density could measure up. There too the technique ("adaptive sampling"?) could be applied in many directions if it really works. Has anybody heard more about this? Unfortunately, I noticed the article while perusing the store rack, and by the time I decided to go back and (reluctantly) buy it the subsequent months issue had come out. I haven't found the issue in my library, and there wasn't too much info in the article anyway. I've been holding out on buying a tape deck, and if this thing is genuinely hi-fi, with the inevitable (?) refinements of any onset technology, it could mean the death of tape decks at least (turntables, CD's? Maybe not, too many people have too much to lose there.). Ken Manheimer {seismo,allegra}!umcp-cs!nbs-amrf!manheimer (Existence is influence. Probably.)
cliff@unmvax.UUCP (01/20/85)
> I noticed in a recent issue of Stereo review (~ 2 or 3 issues back) a single > page article about a prototype of a new audio recorder that had just been > reviewed by the author. PCM machines are available now. > The interesting thing about it was the effective use > of a standard computer floppy (I think 5 1/4", single side, double density) as > the recording medium. With the benefit of what seemed to be an adaptive > sampling technique, over an hour of high fidelity music could be recorded on a > single disk. Three hours can be stored on one L-750 beta videotape with my Nak Digitizer; I believe some companies are trying to get their digitizers to be compatible with all speeds of VHS and Beta which would allow up to 8 hours per tape. > The reviewer said > that, while the sound may not be up to par with CD's, he felt it at least > measured up to any vinyl (or was it any analog medium?) around. The price > mentioned was somewhere near $1000 (1100?). I suspect the quality of sound that I get out of my digitizer is much better than what you would get off a floppy with their box. (i.e. it is a 16 bit 44k sampler). I got my box for $1250 although I believe Techniques selss one for around $800. (Of course you need another VCR, but that shouldn't cost too much more). > Such a thing, if bona fide, has a lot going for it. Foremost is the > opportunity to use it to to record as well as play back - the lack of which is > CD's chief drawback for me, followed closely by their expense. On that count > floppies would be a much a more economical medium once their density could > measure up. Floppies measure up to laser disks...I am not holding my breath. > There too the technique ("adaptive sampling"?) could be applied > in many directions if it really works. ^^ still not holding my breath. > I've been holding out on buying a tape deck, and if this thing is > genuinely hi-fi, with the inevitable (?) refinements of any onset technology, > it could mean the death of tape decks at least (turntables, CD's? Maybe not, > too many people have too much to lose there.). I understand Sony and friends are working on a better resolution VCR. If it catches on you might see more interesting PCM boxes. PCM is here; it works. (I'm not counting on the death of the cassette for quite a while, 8-tracks maybe, cassettes no). > Ken Manheimer {seismo,allegra}!umcp-cs!nbs-amrf!manheimer > (Existence is influence. Probably.) --Cliff [Matthews] {purdue, cmcl2, ihnp4}!lanl!unmvax!cliff {csu-cs, pur-ee, convex, gatech, ucbvax}!unmvax!cliff 4744 Trumbull S.E. - Albuquerque NM 87108 - (505) 265-9143
herbie@watdcsu.UUCP (Herb Chong [DCS]) (01/23/85)
In article <586@unmvax.UUCP> cliff@unmvax.UUCP writes: >> I noticed in a recent issue of Stereo review (~ 2 or 3 issues back) a single >> page article about a prototype of a new audio recorder that had just been >> reviewed by the author. > >PCM machines are available now. > You have missed something, Cliff. This recorder makes no attempt to record all the data. It compresses information to reduce the total data storage requirements, much as compression techniques are used to transmit digital images. PCM's store all the information that occurs up to the bandwidth of the input signal. >> The interesting thing about it was the effective use >> of a standard computer floppy (I think 5 1/4", single side, double density) as >> the recording medium. With the benefit of what seemed to be an adaptive >> sampling technique, over an hour of high fidelity music could be recorded on a >> single disk. > >Three hours can be stored on one L-750 beta videotape with my Nak Digitizer; >I believe some companies are trying to get their digitizers to be compatible >with all speeds of VHS and Beta which would allow up to 8 hours per tape. > We're talking an hour's worth of music on slightly less than 400Kb. That's less than 10s on a PCM recorder. This development has been watched by many in the audio industry as an engineering breakthrough that would greatly lower the bandwidth requirements of a digital recording medium to a point where an ordinary reel-to-reel or high-end cassette deck can be used instead of VCR's. >> The reviewer said >> that, while the sound may not be up to par with CD's, he felt it at least >> measured up to any vinyl (or was it any analog medium?) around. The price >> mentioned was somewhere near $1000 (1100?). > >I suspect the quality of sound that I get out of my digitizer is much better >than what you would get off a floppy with their box. (i.e. it is a 16 bit 44k >sampler). I got my box for $1250 although I believe Techniques selss one for >around $800. (Of course you need another VCR, but that shouldn't cost too >much more). > The sound is reputedly as good as any modern cassette deck without wow and flutter. There are slight breathing effects, but certainly it is hifi, although it may not be good enough to fit into a HIGH-end system. >> Such a thing, if bona fide, has a lot going for it. Foremost is the >> opportunity to use it to to record as well as play back - the lack of which is >> CD's chief drawback for me, followed closely by their expense. On that count >> floppies would be a much a more economical medium once their density could >> measure up. > >Floppies measure up to laser disks...I am not holding my breath. > 'Nuff said. >> There too the technique ("adaptive sampling"?) could be applied >> in many directions if it really works. > ^^ > still not holding my breath. > >> I've been holding out on buying a tape deck, and if this thing is >> genuinely hi-fi, with the inevitable (?) refinements of any onset technology, >> it could mean the death of tape decks at least (turntables, CD's? Maybe not, >> too many people have too much to lose there.). > >I understand Sony and friends are working on a better resolution VCR. If it >catches on you might see more interesting PCM boxes. PCM is here; it works. >(I'm not counting on the death of the cassette for quite a while, 8-tracks > maybe, cassettes no). > As I have said before, PCM has very high bandwidth requirements on the recording medium and any improvements will surely increase it. This approach is from a completely different direction and is based upon well proven physical principles and an accurate electronic model of the way sound is perceived by the human ear. Using this, much useless information can be discarded because the ear is not capable of using it anyway. Although the technology has a long way to go, it is still an interesting and innovative idea that may not fit into audio, but other uses will become apparent soon. Digital voice transmission already uses these techniques for telephone systems, so it was just a matter of time before someone tried to cut costs enough to make it a suitable home digital recording system. It may not sweep the planet, but it may be a stepping stone toward popularizing consumer digital recording. As for the remark concerning home PCM adapters for VCR's, I have information from a reasonably reliable source that Sony is discontinuing their line and making PCM adapters available more or less only for the professional market. >> Ken Manheimer {seismo,allegra}!umcp-cs!nbs-amrf!manheimer >> (Existence is influence. Probably.) > > --Cliff [Matthews] > {purdue, cmcl2, ihnp4}!lanl!unmvax!cliff > {csu-cs, pur-ee, convex, gatech, ucbvax}!unmvax!cliff > 4744 Trumbull S.E. - Albuquerque NM 87108 - (505) 265-9143