EMUSIC-L Digest Volume 19, Number 1 gary numan (2 messages) soundfiles Spinning CDs and stuff like that (15 messages) Virtual Reality (5 messages) Your EMUSIC-L Digest moderator is Joe McMahon . You may subscribe to EMUSIC-L by sending mail to listserv@american.edu with the line "SUB EMUSIC-L your name" as the text. The EMUSIC-L archive is a service of SunSite (sunsite.unc.edu) at the University of North Carolina. ---------------------------------------------------------------------- Date: Thu, 2 Aug 90 14:06:00 EST From: K_KIRSCHNER@ACC.HAVERFORD.EDU Subject: gary numan i am a gary numan aficianado and have pretty much everything he has ever done - i have cds of all his studio albums except `berserker` - however these are the two album per disc comps released - i think - from beggars banquet i've never heard of this `asylum` series - it sounds different from what i have - and quite hitek - anyone have any info on how i can track down copies of it? KenKirschner ------------------------------ Date: Thu, 2 Aug 90 13:14:04 MDT From: Adam Schabtach Subject: Re: gary numan The Asylum series are vastly better than the 2-albums-on-one-disc releases that Beggars Banquet produced previously. Asylum 1 is a four-disc set consisting of his first four albums (The Plan, Tubeway Army, Replicas, and The Pleasure Principle), each with 5-6 extra tracks. Asylum 2 is also four discs, the next four albums (Telekon, Dance, I Assassin, and Warriors), each with 4-6 extra tracks. The extra tracks are live selections, singles and B-sides, etc. with some notable curiousities like 'I Nearly Married a Human (2)' and a solo piano rendition of 'Down in the Park.' Asylum 3 is live material; I'll have to let Metlay tell us about it because he has it and I don't. All of the albums are complete; there are no missing tracks (I sold all my 2-for-1 discs and bought Asylum 1 & 2 because of this). Also included are two booklets in each set. One booklet is all the lyrics for the albums in the box (arranged alphabetically, rather than by album/ track, oddly enough); the other contains reproductions of the album covers, track listings, personnel information, and many photographs (unfortunately captioned in Japanese). Overall the packages are very nicely done. The recording quality is excellent, although I must admit I haven't had a chance to listen to more than a couple of the discs. As for getting them, well, find a CD store that deals in imported discs and ask if they can get them. They were listed as "Gary Numan Asylum 1" or something obvious like that in my dealer's catalog. They're on the Beggars Banquet label, but they're pressed in Japan by Alfa. Good luck! --Adam ------------------------------ Date: Wed, 1 Aug 90 14:20:38 EDT From: ronin Subject: soundfiles ok, a little while ago i asked if anyone here was using Gross/IRCAM soundfiles, and somebody popped up and said "all of IRCAM is!". ok.. real helpful. now that i have asked for some downloadable documentation, i've got silence. whatever happened to that friendly voice in the wilderness? i can't believe either that the docs are proprietary, or that mailing them can be all that difficult. i know they exist in electronic form. is there a charge that i should know about? ----------< Extremism In The Pursuit Of Good Noise Is No Vice >---------- Eric Harnden (Ronin) | V.P., Chief Engineer | Transmedia Music, inc. The American University Physics Dept.| (202) 347-8050 Washington, D.C | ------------------------------ Date: Wed, 1 Aug 90 21:30:00 EDT From: Mike Richichi Subject: Spinning CDs and stuff like that First-year physics will tell you that the outside of a moving disk has a higher linear velocity than the inside. This means that if a compact disk's bits are the same size on all parts of the disk (which they are), and if the disk spins at the same speed (which I'm asking about), more bits will fly by the lens every second when it is on the outside of the disk (near the end) than when it is on the inside. This obviously will mess up the sampling rate. So, my question is, does the compact disk always rotate at the same speed when it is played and this effect get compensated for by different spacing of the bits on the disk or encoding garbage bits that the player ignores, or does the speed of rotation of the disk change depending on what track is being read on the disk, so that the same number of bits per second pass by the lens no matter where on the disk the data is being read from? I am 95% sure that the latter is what happens (especially since I can see a disk spinning more slowly when it is near the end), but I've met with much resistance when trying to convince anyone that the player would actually change the speed at which the disk is rotating. What I need is documentation to prove my point (if I'm right), or documentation to tell me how this is compensated for. Any help anyone has would be greatly appreciated. _____________________________________________________________________________ Mike Richichi, Student Operator, Drew U Academic Computer Center, CM 1411, P.O. Box 802, Drew U, Madison, NJ 07940, USA BITnet: MRICHICH@DRUNIVAC or MRICHICH@DREW UUCP: ...rutgers!njin!drew!mrichich Internet: MRICHICH@DRUNIVAC.DREW.EDU My opinions can't belong to Drew! My opinions make sense! ------------------------------ Date: Thu, 2 Aug 90 09:27:11 EDT From: "Daniel B. Singer" Subject: CD (you're kidding) No, not kidding. The sampling rate IS constant... 44.1 khz, as I recall. The number of bits on a "Track" is not, however. The linear density of the bits along the disk is constant. There are, say, forty zillion bits per centimeter. The laser assmbly moves from the inside to the outside, decreasing speed (to maintain a constant linear velocity, remembering your physics: w = v/r, wr = v, and therefore, if r increases (moving away from center), then w (angular speed (rads/sec; rpm, etc)) mus DECREASE to maintain a constant v) because the constant linear velocity (speed of bits past the read assembly) is required for a constant sampling rate, and minimal buffering. The big buffer is used anyway for error correction. Anywhere on the disk you will find 40 zillion bits per linear centimeter, but there are more bits on the out- side track than the inside track because there are more linear centi- meters there because the radius to the center is larger, and the length of that circle of bits is 2(pi)r. I hate to make this worse, but the data is actually stored in a SPIRAL, with a twice-differentiable function for it all. The motor is infact CONTINUOUSLY changing angular speed, not just in "track" increments, because each track (herein used to mean "circle of bits" not music selection) is really a piece of a spiral, like an LP. DBS ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Daniel B. Singer -- Tuba player masquerading as an Engineer. Return addresses: dbs4@lehigh.bitnet ////// dbs4@ns.cc.lehigh.edu -------------------------------------------------------------------- ------------------------------ Date: Thu, 2 Aug 90 11:57:43 EDT From: Jeffrey R Kell Subject: Re: CD (you're kidding) Hmmm, sounds like I stuck my foot in my mouth. I always thought they were encoded like hard disk media (which damn sure are constant!). I stand corrected with foot in mouth. /Jeff/ ------------------------------ Date: Thu, 2 Aug 90 08:08:45 EDT From: "Daniel B. Singer" Subject: CD Speed is variable, just ask Radio Electronics magazine's "REPAIRING CD PLAYERS" articles. I don't recall what issue. Talk to your local on- line catalog. DBS ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Daniel B. Singer -- Tuba player masquerading as an Engineer. Return addresses: dbs4@lehigh.bitnet ////// dbs4@ns.cc.lehigh.edu -------------------------------------------------------------------- ------------------------------ Date: Thu, 2 Aug 90 15:16:11 EDT From: "Daniel B. Singer" Subject: So which is it? constant linear density or NOT? It is agreed that the linear velocity is kept constant by means of varying the angular velocity (and increasing r...). With a variable speed motor, it really doesn't pay to spread the bits out further on the disk...and it's so much wasted space. You can fit gigabytes on an optical disk... no way you could do that if you spaced out the bits. So which is it? DBS ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Daniel B. Singer -- Tuba player masquerading as an Engineer. Return addresses: dbs4@lehigh.bitnet ////// dbs4@ns.cc.lehigh.edu -------------------------------------------------------------------- ------------------------------ Date: Thu, 2 Aug 90 10:13:21 BST From: Nick Rothwell Subject: Spinning CDs and stuff like that >So, my question is, does the compact disk always rotate at the same >speed when it is played and this effect get compensated for by different >spacing of the bits on the disk or encoding garbage bits that the >player ignores, or does the speed of rotation of the disk change >depending on what track is being read on the disk No documentary evidence, I'm afraid, but I'm pretty sure the disk changes speed. I don't see why this should be too unbelievable to the folks you're trying to convince. My Mac has a variable-speed floppy drive, for example; I don't see why the technology should be that hard. In my CD player, you can hear the speed changing as you cue tracks. This could all be proved by inspection of a Walkman CD player, I reckon, or one of those Marantz monsters that front-loads the CD vertically do you can see it spinning. Nick. ------------------------------ Date: Thu, 2 Aug 90 09:03:28 EDT From: Eric Harnden Subject: Re: Spinning CDs and stuff like that you're kidding. i know that the data from the cd is entered into a fairly substantial buffer as it is read, and i always sort of tacitly assumed that that was how the sampling rate was kept constant. ken pohlmann's got a book out on this. i guess i'll have to go look at it. ----------< Extremism In The Pursuit Of Good Noise Is No Vice >---------- Eric Harnden (Ronin) | V.P., Chief Engineer | Transmedia Music, inc. The American University Physics Dept.| (202) 347-8050 Washington, D.C | ------------------------------ Date: Thu, 2 Aug 90 08:14:00 PDT From: DAVE HOWELL Subject: Re: Spinning CDs and stuff like that A CD will rotate approximately 500 RPM when it starts (at the center), and drop to about 200 RPM at the edge. This is from the CD book Sony published. Heavens. I thought everybody knew that. :) ------------------------------ Date: Thu, 2 Aug 90 09:10:15 MDT From: Adam Schabtach Subject: Re: Spinning CDs and stuff like that > This could all be proved by inspection of a Walkman CD player, I reckon, I happen to have a Discman, as well as a 70 minute disc that's painted half black, divided across its diameter. Perfect setup for a little empirical observation: As expected, the disc definitely rotates more slowly as it plays. The difference is quite dramatic if I start with track 1, play it a bit, then skip forward to the last track. Unfortunately I can't give any quantitative measurments, not having a stroboscope handy. --Adam ------------------------------ Date: Thu, 2 Aug 90 12:56:00 EDT From: METLAY@PITTVMS.BITNET Subject: Re: Spinning CDs and stuff like that You have a 70 minute CD painted half black across the diameter? Now where the heck would you find something like that, fer Gosh sakes? |-> metlay PS> For those of you who weren't in on this little joke, here's a bit of news from the Emusic world: in a rare but appreciated move, a Japanese record firm has purchased the rights to the entire Beggars' Banquet Gary Numan catalog, and has released it as a series of eight CDs in two four- disc sets, entitled Asylum 1 and Asylum 2. (Asylum 3 is a single live CD) The sound quality is delightful, and the CDs provide a means of archiving Gary's work completely and cleanly on digital media. So when are they going to do this for Tangerine Dream, Jean-Michel Jarre, Yes, ELP, Renaissance, Steve Hillage, etc etc etc? And all of the CDs are painted as Adam described them.... ------------------------------ Date: Thu, 2 Aug 90 11:48:31 EDT From: Jeffrey R Kell Subject: Re: Spinning CDs and stuff like that The bit rate is constant, just like an LP has consistent-speed analog recording. Altering the motor speed would be an engineering bitch, you are after consistent speed (in analog terms, minimizing wow/flutter) which would go out the door if it were variable speed. CDs (and digital disk media) are designed with the innermost track as the limiting factor, and outer tracks just record with less density. The bit rate is constant. /Jeff/ ------------------------------ Date: Thu, 2 Aug 90 12:05:00 PDT From: DAVE HOWELL Subject: Re: Spinning CDs and stuff like that The bit rate is constant. Ever heard about Video laser disks? There are two kinds: CAV and CLV. Constant Angular Velocity has each frame take one track. This allows freeze frame, etc. The outer tracks are stretched because they travel at a higher speed. CLV has all tracks at the highest possible density, and the disk slows down as it gets nearer the edge. This allows more material, but because frame beginnings are sprinked all over the disk, freeze frame will jump, slo-mo won't work, etc. CD's are CLV. The 'engineering' to do this is a piece of cake. Motor speed is servocontrolled by bit rate. If the bits are coming off the track to fast (>88.2KHZ+ (stereo, and control bits, oops, and error correcting bits)) the moter slows down. If the bits are to slow, the motor speeds up. The large buffer necessary for the error correction system also allows variations in the bit rate to a certain extent. The servocontrol for this is trivial compared to the work necessary to keep the surface of the CD in focus! ------------------------------ Date: Mon, 6 Aug 90 14:13:39 EDT From: Joe McMahon Subject: Administrative fiat Okay all, enough about CD control mechanisms. Has anyone out there actually managed to find a version 2 VFXsd? Are the piano sounds really as great as all that? Has anyone else tried to get an upgrade? No chips for me yet -- but I'm supposed to call the shop today. --- Joe M. ------------------------------ Date: Mon, 6 Aug 90 11:32:32 BST From: "Benjamin M. J. Ellis :->" Subject: Spinning CDs and stuff mike that Hmmm... Firstly, about this speed change, the CD should go FASTER as it gets to the end if what you say is true (since, as far as I remember, the CD plays from inside to outside). Anyway, enough of humouring you, I'm fairly convinced, by what little I remember of the last CD control mechanism I looked at, that the disk spins at the same speed, so I think you'll find that actually the bit spacings change (if not the size of the bits), of course this could all be totally wrong, but from an engineering point of view, changing the speed of the disk would seem a little bit of a silly thing to do, mind you, we are dealling with a phillips invention 8-) Sorry to add confusion, Benjamin. U.K.C> England -------------------------------------------------------------------------------- Engineering is the fine art of balancing dreams against life's harsh realities. ------------------------------------+------------------------------------------- E-mail: bmje.ukc.ac.uk : Snail Mail: B.M.J. Ellis, University of Kent : 33 Parkfield, at Canterbury : Chorleywood, England : Herts. WD3 5AZ ------------------------------------+-------------- England -------------------- "Today I am a small blue thing, like a marble or an eye... I am cool and smooth and curious, I never blink, I am turning in your hand, turning in your hand small blue thing..." - Suzanne Vega. -------------------------------------------------------------------------------- ------------------------------ Date: Mon, 6 Aug 90 12:07:26 MDT From: Adam Schabtach Subject: Re: Spinning CDs and stuff mike that > Anyway, enough of humouring you, I'm fairly convinced, by > what little I remember of the last CD control mechanism I > looked at, that the disk spins at the same speed, so I think > you'll find that actually the bit spacings change (if not the > size of the bits), of course this could all be totally wrong, Next time you happen to be in Boulder, Colorado, USA :-) you can stop by and watch my Sony Discman. The disk spins slower as the laser approaches the outside edge of the disk. Period. It's a dramatic change. Weird or not, that's how it's done. (I wanna know how they keep the laser focused on the bit stream -- I mean, those bits are SMALL!) --Adam ------------------------------ Date: Wed, 1 Aug 90 07:13:17 EDT From: Rob Camp Subject: Virtual Reality I am very excited about virtual reality, but I realize that it is still hype. What makes VR so exciting it that it has the potential to change the way we view musical performances. VPL Research, in Redwood City CA, is one of the leading firms venturing into this artificial world. It's founder, Jaron Lanier, coined the term "virtual reality", and he has been the subject of many magazine articles. VPL's data glove may be the technological invention to evolve electronic musical performance. It may free musicians from the physical restraints of the keyboards. VPL is developing a whole body data suit. This has the potential to change the way we view dance performance. The style of my music is dancemusic. I am seeking new methods of performance that breaks with tradition, yet provides excitement, visual style, and entertainment. I have been excited about dancemusic's surge in popularity, and it's relative acceptance by the critics. However, if dancemusic is to become a legitimate musical style, such as jazz, C&W, Rock, etc.., the musicians must develop creative methods of performance that links the music with it's technology. This is where virtual reality has potential. I believe the data glove may be the most significant music technology invention since the electric amplification of the guitar. Rob Camp George Washington University ------------------------------ Date: Wed, 1 Aug 90 09:17:12 MDT From: Adam Schabtach Subject: Re: Virtual Reality > I am very excited about virtual reality, but I realize that it is still > hype. What makes VR so exciting it that it has the potential to change > the way we view musical performances. VR or no VR, I'm still gonna view musical performances the same old way: with my eyes... :-) But seriously, I'm very excited by VR too, but I'm not quite sure I follow what you're envisioning. I can see how it might have some great applications for performance, but only from the perspective of the performer. Somehow I don't think it's going to be terribly interesting to watch someone wander around on stage wearing a data suit, experiencing their own VR -- how does the audience relate to a reality they can't perceive? Now, if one could get everyone into the VR (maybe with everyone wearing the projection helmet, but not the suit, so the performer was "driving" the reality), it could be very interesting, but probably prohibitively expensive. Just projecting the VR onto a screen over the stage isn't really going to do it, I don't think. (This can already be done with available technology: an Amiga, a video camera, and a program called Mandala, I think. A performer stands in front of the camera and the computer creates an animated image of him/her, superimposed on another image containing pictures of instruments. The performer can "touch" the video instruments, generating MIDI events which trigger synthesizers. Also c.f. Laurie Anderson's drum suit, as seen on the "Mister Heartbreak" tour, and recorded on film in "Home of the Brave.") > I believe the data glove may be the most > significant music technology invention since the electric amplification of > the guitar. As an alternative to traditional controllers? There are lots of controllers that have never been widely accepted and exploited; I'm not sure I understand what makes the data glove different. I don't see dance bands like Erasure and Janet Jackson taking to the stage waving Air Drums or Gun Drums. Air Drums provide lots of axes of control (eight or so per hand), implement a "virtual instrument" of sorts, and are available today (unless the company went under for lack of sales). The Thunder looks like one of the greatest things to happen to musical control, but we have yet to see if it catches on. I think the most significant music technology invention award would have to go to MIDI before it goes to VR. I'm not trying to get on your case here; I'm interested in discussing what you have in mind. I'm no particular fan of traditional controllers, and I'm very interested in what VR might have to offer to music. --Adam ------------------------------ Date: Wed, 1 Aug 90 12:03:00 EDT From: MICHAET@CLEMSON.BITNET Subject: Re: Virtual Reality On Wed, 1 Aug 90 07:13:17 EDT Rob Camp said: > I am very excited about virtual reality, but I realize that it is still > hype. What makes VR so exciting it that it has the potential to change > the way we view musical performances. VPL Research, in Redwood City CA, Can you be more specific about whar VR is? What kind of information does a data glove transmit? Would you control pitch, duration, and other parameters with hand movements instead of a keyboard? I have no problem with traditional keyboards, and I am not a dance enthusiast. However, the datasuit idea is fascinating. The dancer produces his or her own music. Hmmm... This reminds me of an Ondes Martenot. Can somebody give me more details on that instrument? Speaking of instruments, just what is a lyricon? I have a couple of Shadowfax and Osamu (the source) albums, and I am trying to figure it out. Thanks, Michael Townsend ------------------------------ Date: Wed, 1 Aug 90 15:23:00 EDT From: Craig Hicks Subject: Virtual Reality >the subject of many magazine articles. VPL's data glove >may be the technological invention to evolve electronic >musical performance. It may free musicians from the >physical restraints of the keyboards. VPL is developing >a whole body data suit. This has the potential to change >the way we view dance performance. What I'd like to see is a keyboard controller that could be used to choreograph and manipulate virtual dancers...[wink, wink]...but seriously folks, I could get a lot more excited about virtual reality-based systems if there were some actual virtual instruments out there, rather than gizmos that allowed use of existing MIDI tone generators via "virtual control." An instrument that had some sort of integral vr interface that allowed, among other things, software control of voice architecture. So far, anyway, the notion of being able to play my TX81z by waving my hand around as opposed to using a conventional keyboard or a wind controller just doesn't float my boat. But I must admit that I am much more of a recordist than a live performer. For people who do a lot of performance, such a scheme could be just the ticket. /craig ------------------------------ Date: Wed, 1 Aug 90 21:05:24 GMT From: "R. Raisch" Subject: Re: Virtual Reality MICHAET@CLEMSON.BITNET writes: >On Wed, 1 Aug 90 07:13:17 EDT Rob Camp said: >> I am very excited about virtual reality, but I realize that it is still >> hype. What makes VR so exciting it that it has the potential to change >> the way we view musical performances. VPL Research, in Redwood City CA, > Can you be more specific about whar VR is? > What kind of information does a data glove transmit? > Would you control pitch, duration, and other parameters with > hand movements instead of a keyboard? > Thanks, > Michael Townsend The current issue of Byte magazine has a very good article on the ``data-glove'', as well as other ``gestural input devices''. The data-glove uses fiber-optic strands across the various knuckles of the hand which when bent, (flexed), vary the amount of transmitted light through the fibers. In it's full implementation it also uses a positional sensor based on magnetism. The data retrieved from the glove includes flexure data per knuckle, and position in 3-space. Unfortunately, the data-glove retails for as much as many new automobiles. Another possibility is the Matell (Nintendo) Power-glove, which has MUCH less discrimination, but costs around $100 US. The Byte article contains schematics and code to interface the Power-glove to a PC style micro. (Through the parallel printer port). I would be very interested in any information from someone who has a Power-glove and is using it to control anything through a micro. (I have *BIG* plans for this widget. ) I'd also be willing to abstract information from the Byte article for anyone interested in this technology. -- Robert Raisch - TechnoJunkie & UnixNut| UseNet: {uunet,mailrus}!frith!raisch Control Technology Corporation | InterNet: raisch@frith.egr.msu.edu Hopkinton, MA | ICBMNet: 084 28 50 W / 42 43 29 N "I *have* no ideals. I lost them on my travels." - Dangerous Liasons ------------------------------ End of EMUSIC-L digest ******************************