Talk:LaserDisc/Archive 1
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Archive 1 | Archive 2 |
Analog or Digital
I've heard more than once that the LD is actually completely analogue (at least for the video part, if not the audio), rather than digital like the CD. Can anyone knowledgable confirm and add info about this? --radiojon 07:29, 3 Sep 2003 (UTC)
- That's my knowledge as well - a quick google found the following short technical description [1]. andy 07:39, 3 Sep 2003 (UTC)
- I have read more than once that audio could be analogue or digital, but video was always the same(i forget which). What I never understood is: how on earth do you store analogue signal by anything other than depth(as in a record read by a needle)?Boffy b 00:12, 2004 Sep 26 (UTC)
- I think this is how it works. The video signal is used to frequency modulate a carrier signal, and the resulting signal is clipped and stored on the disc as a square-wave-like signal. Each transition from pit-to-land or land-to-pit represents a transition of this FM video signal from positive to negative, or vice versa. When the signal is read off of the disc, the harmonics are filtered out, turning the square wave back into a modulated sine wave, which is then demodulated and turned back into video. Someone correct me if I'm wrong. --Arteitle 06:10, Sep 26, 2004 (UTC)
- Yes, from what I remember reading about LD a while back in a book about TV & video systems, this sounds right. The space between the pits on a LD represents the FM-modulated space between the "peaks" and "valleys" of the waveform representing the whole carrier (video, audio, and all). Basically, it's a form of analog Pulse-width modulation,or PWM. -- misternuvistor 03:24, 11 October 2005 (UTC)
- This needs to go in the article. The whole reason I came to this article was to learn how LDs work, and we have this huge article that doesn't tell you that. But seeing that this discussion was in 2005 and I'm just as lazy as everyone else, I'm not going to do it either. I've already learned what I came for, one way or another. :-). Mbarbier (talk) 21:16, 28 May 2009 (UTC)
- Yes, from what I remember reading about LD a while back in a book about TV & video systems, this sounds right. The space between the pits on a LD represents the FM-modulated space between the "peaks" and "valleys" of the waveform representing the whole carrier (video, audio, and all). Basically, it's a form of analog Pulse-width modulation,or PWM. -- misternuvistor 03:24, 11 October 2005 (UTC)
- I think this is how it works. The video signal is used to frequency modulate a carrier signal, and the resulting signal is clipped and stored on the disc as a square-wave-like signal. Each transition from pit-to-land or land-to-pit represents a transition of this FM video signal from positive to negative, or vice versa. When the signal is read off of the disc, the harmonics are filtered out, turning the square wave back into a modulated sine wave, which is then demodulated and turned back into video. Someone correct me if I'm wrong. --Arteitle 06:10, Sep 26, 2004 (UTC)
Here's a diagram (below) I made a long time ago that shows clearly how the audio modulates the video and the sum is clipped and the pits created - click to see the large version.
Ty Chamberlain (talk) 16:57, 18 July 2010 (UTC)
LD FAQ link
> I've heard more than once that the LD is actually completely analogue
http://www.access-one.com/rjn/laser/legacy/ld96.html
The article author might want to link to the hosting page for the above, as there are numerous FAQs, some more recent than those linked from the wik article.
http://www.access-one.com/rjn/laser/laserdisc.html
Resolution is measure of VERTICAL Lines
When you talk about a video resolution in terms on LINES, this refers to an old analogue mesaurement system where you determine the number of vertical high-contrast lines you can resolve. "400 lines" refers to 400 vertical lines could be distinguished (this would correspond to about 800 pixels across) compared to the 250 lines (about 500 pixels) of VHS under ideal conditions. For this reason, I changed the section that talked about resolution from saying "HORIZONTAL" lines to "VERTICAL" lines. Don't confuse resolution with the number of "SCANLINES" a format uses. Swirsky
As far as i know, the resolution "400 lines" for laserdisc means 400 pixels horizontally - 200 line pairs (to use the correct term of the analogue world), while VHS hast about 250 lines/125 line pairs. In the following section of the text someone got it wrong:
"The image resolution is also greater for DVDs for two reasons. Firstly, NTSC laserdiscs offer 400 lines of resolution while DVDs offer 480 lines. PAL laserdiscs offer 440 lines of resolution while DVDs offer 576."
480 lines NTSC and 576 lines PAL mean VERTICAL lines and have nothing to do with the horizontal resolution - even the worst VHS offers 480 lines (NTSC) and 576 lines (PAL) in the vertical dimension. Theoretically, DVDs offer a full resolution of 720 lines (horizontal), but a comparison to the 400 lines of the Laserdisc makes not sense at all, because of digital compression (DVD) and limitation of sharpness/Aperture correcture due to noise (Laserdisc). (MalteRuhnke, German Wikipedia)
- Jesus H. Christ on a pogo stick, you are both so utterly wrong. In the video world, HORIZONTAL resolution is known as COLUMNS, while VERTICAL resolution is known as LINES or ROWS. This means that the computer resolution of XGA is exactly 1024 columns wide by exactly 768 lines tall. ALL raster video images are made up of PIXELS, including NTSC/PAL/SECAM/VGA/whatever, which means that a pixel is a pixel no matter the system.
- This definition still stands whether or not the image is progressive, interlaced, overscanned, analog, "digital", RGB or YPbPr.
- All home video and television systems always have the exact same horizontal resolution (columns) as the TV system (I.E.: either NTSC or PAL/SECAM) they're using, their visual granularity differed ONLY in terms of vertical resolution (lines or rows).
- I'll dig up the actual resolutions of the different formats sometime and update the article. 207.177.231.9 16:44, 20 July 2007 (UTC)
- You're the one who's wrong. Horizontal resolution is often expressed in lines or line pairs, in which case they mean vertical lines of course. Furthermore, analog video is not composed of pixels. Pixels are discrete units, analog video varies infinitely (the actual information is constrained by bandwidth and noise). MalteRuhnke is correct, however he uses the incorrect term "Vertical lines" when referring to vertical resolution, when the vertical resolution would be defined by _horizontal_ lines. 400 vertical lines (a measure of horizontal resolution) corresponds to 400 pixels. Your last paragraph is also wrong. _Vertical resolution_ often doesn't change (480 or 576 visible lines depending on which broadcast system was used). Horizontal resolution can vary depending on the bandwidth. TV broadcasts have more bandwidth than VHS for example, so VHS has worse horizontal resolution. Totsugeki 00:59, 16 August 2007 (UTC)
- (1) Please don't use curse words. It's rude. (2) Horizontal resolution is measured by drawing a perfect circle on the screen, and filling that circle with vertical lines. (3) You then count left-to-right to see how many lines can fit inside that circle without blurring into a grey smudge. (4) The result is expressed as "420 lines horizontal per picture height". (5) If you want to convert that value to digital terminology, just multiply by 4/3, which yields approximately (key word) 560 pixels edge-to-edge, horizontally.
- The vertical resolution is fixed by the number of scanlines. i.e. 486 for NTSC, 576 for PAL, 720 for ATSC-progressive, or 1080 for ATSC-interlace. - 15:37, 11 October 2007 (UTC)
- I reviewed my comment and can't find any curse words. I agree with the rest of your comment, except that ATSC-progressive can also be 1080 lines (see the ATSC article). I did say the exact same thing: vertical resolution depends on the TV system. The comment I responded to contained this completely incorrect statement: "All home video and television systems always have the exact same horizontal resolution (columns) as the TV system (I.E.: either NTSC or PAL/SECAM) they're using, their visual granularity differed ONLY in terms of vertical resolution (lines or rows).". Totsugeki 16:31, 11 October 2007 (UTC)
- The resolution section has been completely butchered as an unfortunate casualty of the above disagreement. Some of you are confusing lines and columns. DVD resolution, for instance, would be a maxium of 480 lines (720x480 digital resolution), not 720 columns. Much more comparable with LDs 450 line performance.
- TVL is a measure of horizontal resolution. Additionally, TVL is a measure of horizontal lines per picture height, so the aspect ratio must be considered- DVD does not use square pixels so its TVL is closer to a max of 405 for 16x9 content and 540 for 4x3 content. This section SHOULD read as follows:
- "...560×480 (425 TVL): LaserDisc (440 TVL with PAL LaserDiscs), S-VHS, Hi8 (LaserDisc had 120-lines of horizontal NTSC color resolution: later LD's had even higher color resolution, up to 240 lines. S-VHS and Hi-8 had 30-lines, maximum.)
- ...
- 720×480 (540 TVL 4:3 or 405 TVL 16:9): DVD (incl. anamorph and letterbox widescreen), MiniDV, Digital8, Digital Betacam (professional), digital broadcast (though often video is downsampled to 480, 528 or 544 pixels horizontally in order to compress it better and so offer more TV programs per channel and/or save on broadcasting costs)"
- [All the TVL measurements below this point need to be corrected.
- I'll leave it up to someone else to correct the article.—Preceding unsigned comment added by 70.162.47.152 (talk) 18:48, 24 October 2010 (UTC)
Not all of the above is true
The Total Rewind VCR museum has the whole story, but in short it was released in 1980 as DiscoVision/LaserVision/VLP(30cm, all analogue, flopped), in 1988 as CD-V(20cm, digital CD sound, analogue video, flopped), and in 1991 as LaserDisc(same as CD-V, but 30 cm and sometimes with analogue audio as well, fairly successful).
Read all about it at [2]
- No, DiscoVision was released in 1978 along with a Jaws disc. —Precedingunsigned comment added by 67.239.10.227 (talk) 02:54, 22 August 2009 (UTC)
The LaserDisc/LaserVision format was released to the public on November 15, 1978 at 3 stores in Atlanta, GA. Magnavox (Philips) produced the player, called Magnavision, while MCA DiscoVision (Universal Studios) produced the discs. There was no 'official' format name at the time - Philips called it VLP or Magnavision, while MCA called it MCA DiscoVision or DiscoVision - usually, it was referred to as the Reflective Optical Videodisc. It wasn't until late 1980 that the name LaserVision was standardized by Philips, MCA and Universal-Pioneer (a 50/50 joint-company owned by Pioneer Electronics and MCA, Inc.) as the name of the format. The name LaserDisc was a Pioneer owned trademark used to refer to its own brand of LaserVision compatible players and discs so, at the time, a Magnavox player was NOT a LaserDisc player, it was a LaserVision player. In the early 90's, it became the name of the entire format. Anyway, at the launch in Atlanta, there were around 50 individual titles available from a catalog of 200 listed. Jaws was among them, as well as Animal House (an EXTREMELY rare CLV Extended Play pressing), plus many other films and educational titles. Disc prices ranged from $5.95 to $15.95. Those first discs played pretty well, having been individually inspected by MCA DiscoVision before being packaged and sent to Atlanta - a month later, as software sales increased in Atlanta and the format was launched in Seattle, disc defects started showing up in great numbers because MCA was unable to inspect every single disc pressed. 2 our of 3 discs in a 5-sided box set were typically defective and at the MCA DiscoVision plant itself, the defect rate ran 70% to 90% on an average day. In April of 1979, in an attempt to reduce the number of defects coming off the presses and increase the number of 'good' discs shipped to Atlanta and Seattle, MCA DiscoVision relaxed the disc standards in many areas. As one example, the allowable levels of birefringence; originally, it was no more than plus or minus 10 degrees, 20 total and MCA relaxed that standard to 40 degrees, 80 total. They neglected, however, to tell Magnavox/Philips about this for almost a year, meaning that for the first year the format was on the market, the discs and players weren't totally compatible! Pioneer knew however, and the DiscoVision designed/Pioneer built PR-7820 and co-designed Pioneer VP-1000 were compatible with their 'relaxed standard' discs and able to play them perfectly. BTW, I say 'co-designed' for the VP-1000 because MCA DiscoVision engineers had a direct hand in the design of the consumer VP-1000. Much of its circuitry was based on the PR-7820, which was the only player to incorporate ALL of MCA DiscoVision's design preferences, such as playing the disc with the laser on top and moving the disc itself, instead of moving the laser, for tracking. The Pioneer LD-1100 and LD-660 were also 'co-designed' by MCA DiscoVision. They were also not technically Pioneer Electronics players, so even though they said only "Pioneer" on the front, they were Universal-Pioneer players - in fact, they (and the VP-1000) have stickers on the back of them with the DiscoVision logo triangle stating that that player had passed MCA DiscoVision's quality control - it was kinda like the "THX" program at the time. The logo is the original Disco-Vision triangle with the Pioneer tuning-fork logo inside of it. Below is one I've drawn of the Universal-Pioneer logo. Many people, even the most fanatical LD collectors and fan-bois, do not know this about those players. That's one of the reasons they were so much better, in both picture and tracking quality, than the Magnavox Magnavision VH-8000 and VH-8005 and the Sony VDP-1000 industrial uplayer. If you own a Pioneer VP-1000, 1100 or 660, look on the back of the player, around where the power cord comes out, for a TINY sticker saying "Universal-Pioneer QC Passed" with the DV triangle in metallic gold. Ty Chamberlain (talk) 17:41, 18 July 2010 (UTC)
File:Universal Pioneer Logo (Tuning Fork and Triangle).jpg
One quick note - the LD system only flopped, and had multiple-relaunches, in the U.K. and Europe. In Japan and America LD was continuously available to consumers from the original launch dates until the formats death in the early 2000's. While it was moderately successful in America, in Japan is was an outright blockbuster because, until the mid 90's, it was illegal to rent software in Japan - thus, the high price of movies on Beta and VHS kept software sales low. The low prices of LD's lead to explosive growth right from the start and Japan had the highest disc title count of any country. Within the first year of LD's launch in Japan, 1982 to 1983, there were over 1000 titles available to consumers. It took until 1986 to reach that many titles on LD in America. Ty Chamberlain (talk) 17:49, 18 July 2010 (UTC)
YOU'RE LAST PARAGRAPH IS WRONG
You thought it was illegal to rent software in Japan until the mid 90's? What a bogus opinion. Video rental shops have been around in Japan since the late 70's. Video rental shops in Japan rented out both Beta and VHS at first, then mostly VHS and laserdiscs from the mid 80s onward. The reason why the laserdisc had somewhat moderate success in Japan was due to the knowledge of what was a desirable format, knowledge gained from advertisement and detailed articles in audio/video magazines and showroom floors. To make a quick story short, the Japanese consumers where more educated and knew what was better. — Preceding unsigned comment added by 119.172.121.99 (talk) 23:54, 9 October 2011 (UTC)
More
Laserdisc is an entirely analog format where the video portion is concerned. Some people find Laserdisc slightly more attractive than DVD because it does not suffer from compression related issues and has a smoother more "film like" image. However, it was also prone to issues such as "crosstalk" which DVDs do not suffer from and DVD has 30% greater overall resolution. In addtion, Laserdiscs had the capability to store digital audio, a capability that was regularly made use of in the early and mid 1990s, up to 1997 or so when the format finally died. Dolby Digital and DTS debuted on the Laserdisc format. I have several websites earmarked which contain information on the development of Laserdisc, catalogs of titles that were released and even lists of which titles contained Dolby Digital and/or DTS sound. If you are interested, or have a general question, I can be reached via e-mail at OneActor1@aol.com
- "Some people [videophiles] find Laserdis slightly more atractive than DVD..." These people are the video counterpart to audiophiles thay favour vinyl over CD, arn't they.
- In the line "NTSC discs could carry two analog audio tracks, plus two uncompressed PCM digital audio tracks, which were generally CD quality or better." I was wondering why you added "or better" after the description of "CD quality". As I mentioned in my earlier edit comment, the specs for Laserdisc's PCM tracks are the same as CD: 44.1 kHz, 16 bit, stereo. --Arteitle 19:34, Nov 13, 2004 (UTC)
- CDs aren't compressed (PCM). Also high quality tapes are arguably better analog quality then vinyl. Nil Einne (talk) 11:28, 23 February 2008 (UTC)
It was my understanding that the nature of LD-Audio storage allows for higher than CD audio quality. This is laregly the result of the audio being uncompressed, where it is compressed on CD. Basic listening tests have led me to believe that this is both possible, and in some cases true. Although I suppose that this could be the result of mastering differences.
- Your post is largely true and informative, except for the bit about CDs. Standard music CDs are uncompressed, but both the video and audio on DVDs is compressed which may be what you are referring to. Boffy b 20:51, 2004 Nov 15 (UTC)
- That doesn't make any sense. The audio on CDs isn't compressed. Nil Einne (talk) 11:28, 23 February 2008 (UTC)
The audio on DVD's doesn't have to be compressed either - the format is capable of carrying linear PCM like the CD and LD formats. Also, in addition DVD has double the color resolution as LD - and it's full 250-line, 3-color resolution, not 40 lines of 3-color and 80 lines of orange-cyan 2-color like LD (NTSC). Don't get me wrong, I love LD, but to say it's video is 'uncompressed' is silly - the NTSC format it carries IS highly compressed as compared to a progressive scan, component source image from DVD. Ty Chamberlain (talk) 17:55, 18 July 2010 (UTC)
Comb Filtering
Comb filters are a way of keeping chroma subcarriers from interfering with luminance signals (as a beat pattern) *when you mix them*. Clearly, if you're taking the video off the S-Video connector, that's not an issue.
If you can find a citation that the comb filter was explicitly intended to make the S-Vid out look better (as opposed to the composite out) which is *not* marketing material (:-), please post it, and I'll retract. Baylink 07:14, 4 Dec 2004 (UTC)
- The reason a comb filter is always in the signal chain with LD is because the video is stored on disc as a composite signal. So using the S-Video output of a LD player means separating luma and chroma in the LD player (and using its comb filter), whereas using the composite output of the LD player means separating them in the TV (and using its filter). See [3] (part of the LD FAQ). --Arteitle 13:32, Dec 4, 2004 (UTC)
- Well, I will be dipped in shit. I had managed to completely miss that it's composite on disc. Nice reference, BTW; is that in the main article? Baylink 22:19, 4 Dec 2004 (UTC)
- Yow, don't take it so hard. :) Yeah, it's in the external links. --Arteitle 23:12, Dec 4, 2004 (UTC)
DVL-919
The DVL-919 is still on Pioneer North America's website but is NOT in production any longer. It's been out of production for the U.S. since around 2000. I verified with several Pioneer dealers, I also verififed that a few units are "floating about" but that Pioneer no longer consideres it a current model. The Laserdisc section of the 919 was borrowed from an older player in the CLD-600 series, which were never very good players and the DVD section is mediocre at best in comparison to most new units from Pioneer, Toshiba, etc... and Pioneer made the decision to drop it when support for LD fell through completely in the U.S.
- Fine. But please *correctly* characterize your changes, don't take the website reference out of the article completely... and sign your damn changes. :-) Baylink 22:15, 5 Dec 2004 (UTC)
I don't understand how I'm failing to properly characterize my changes. The reference to the DVL-919 being on the website is moot and doesn't need to be in the article. On the site or not, the manufacturer consideres the player dead and says they've ceased all production, as of 4 years ago. In any case, I'd sign my changes if I knew how, but I don't. I'm not entirely sure why it matters, it's not as if I'm filling the article with derogatory comments or bad information. You guys that desperate to track me down?
- No, it's simply what one does. Since you're not signed in, you haven't anything to sign as, anyway. But don't be surprised if your lack of desire to set up an account and take responsibility for your changes makes them slightly less important to others.
- There is no clear public evidence that the manufacturer considers the item dead: this is an encyclopedia; we don't do primary research. "Private communication" is not an acceptable source. As slow selling an item as it is, ceasing production 4 years ago doesn't at all have to mean that they don't have them available in their channel. Baylink 19:10, 10 Dec 2004 (UTC)
I won't debate this with you any more. I'll only add that any member of the public need only contact a local retailer or consult Pioneer directly to find that the 919 is a non-production unit and is no longer supported by the manufacturer. It's an obvious case of a company failing to update a portion of their website. Slow sales has nothing to do with the situation, this is not an issue of a manufacturer cutting back production numbers in response to waning demand, it is an issue of ceased production. The 919 is no more current than a 1995 Corvette, on the website or not.
- All of which is immaterial to the fact that the information in question is primary research, and thus not fit for Wikipedia. And "is no longer supported" is not a subset of "no longer for sale", either. Clarity, please... :-)
- My DVL-919 has a manufacture date of December 2003. So it certainly was NOT discontinued in 2000.
- In fact, contrary to the claims above, manufacture of the DVL-919 continued until a final production run announced on January 14, 2009. [1]. All the more reason not to trust primary research or private communication.
Disruptive technology?
- When they were first introduced, laser discs were believed to be disruptive technology, a promise they failed to fulfill.
The term "disruptive technology" was not coined until 1997. Can you call LD the "disruptive technology"? -- Toytoy 08:44, Feb 6, 2005 (UTC)
The term didn't exist in the 1980s, true, but the concept was there in the marketing. There was a clear belief on the manufacturers' part that it would supplant videotape due to superior picture quality.
Perhaps it should be amended to "what would later be described as ..." — Daniel Case 05:20, 4 Jun 2005 (UTC)
- In order for a new technology to be disruptive, there needs to be an already-existing standard that dominates a market. For example Compact Cassettes: In the late 70s, the newbie known as cassette overthrew the dominant tech known as the phonograph, and the Cassette became the preferred choice of consumers, thus the cassette was "disruptive". Getting back to laserdiscs: In 1978, there was NO dominant video technology. - Theaveng 15:43, 11 October 2007 (UTC)
Laserdisc Introduction
By the time the format was brought to market in 1978, the hyphen was removed from the format name. They marketed it under the name DiscoVision beginning December 15, 1978 after the earlier CRV disc format had died out in obscurity.
Could more knowledgable members please rewrite, delete, or elaborate on what "the earlier CRV disc format" was that died out? Just to be sure, what does "CRV" stand for?
There's some minimal expansion on what CRV was in the variations section of the page, which I've already sort of been thinking of moving because it isn't really a variation of Laserdisc, it's an earlier format. IMO, anymore info on CRV than what's already here should be on a CRV specific page, as the minimal reference to and explanation of the format that are on the LD page are all that are really neccesary in context to the Laserdisc format, which was a seperate entity.--Flash-Gordon 11:01, 23 May 2005 (UTC)
That scroll button is going to be the death of me... but I digress. I found the passage in conflict to that I know about history of video discs: I initially thought that the "earlier CRV disc" as a reference to RCA's CED format (or some other obscure/still-born format of the time). When "CRV" is defined later in the article, it seems a anachronism that recordable video discs where available around the time of Laserdisc's introduction. If I am wrong, could some please enlighten me? --Kevin586 22:03, May 23, 2005 (UTC)
a long time reader first time writer adds: the CRV comment early in the article is confusing, especially since it's not explained until the (very) end. I agree with kevin that it's mostly irrelevant. Another unrelated thought: perhaps it's worth mentioning (or linking to) the Dune laserdisc where the rare/high demand discs are mentioned; the "six hour version" (which is really only about four hours) is only available on japanese LD, and not all the SFX are "finished".
-- cz May 25, 2005
Kevin - CRV discs were recordable (with the proper equipment) caddy-discs (see the picture in the article) originally intended for use as A/V carriers like Discovision/Laserdisc. The format proved a failure for multiple reasons and AFAIK, was unrelated to CED, although it did find limited use as a backup medium before tape drives, ZIp and JAZ drives and recordable CD media was avaliable. I added the comment about the "earlier CRV format" because, as it was explained to me, the movement from MCA into Discovision was largly driven by the failure of the CRV format. I know fairly little about the CED and CRV formats in practice, but if the consensus is that the CRV reference should be removed, modified or moved to a seperate page (which is where I'm leaning) than that's what should be done. --Flash-Gordon 09:00, 31 May 2005 (UTC)
- Yes, Flash-Gordon is right, but CRV, AFAIK, was not the name for the prototype MCA/Universal/Discovision LD system released in 1972, nor was it another name for RCA's CED system (which was either known as CED, or SelectaVision). CRV was a recordable system developed by Sony in the late 80's-early 90s and it's official name is "CRVdisc". Plus, I don't think there were any pre-recorded CRVdisc releases at all, as mentioned in this talk page under the WORM? heading (and in the main article as well), because CRVdisc wasn't really marketed as a consumer format. CRVdisc was mainly a professional/industrial format, due to it's high cost. misternuvistor 21:39, 11 December 2005 (UTC)
The CRV, Component Recordable Videodisc, invented by Sony, did NOT become available until the early/mid 1980's. It used a Time-Compression-Integration (TCI) signal with digital audio. There were NO optical disc formats other than LD/LV, available for use (by industry or consumers) in the 1970's. By 1986 the LaserVision/LaserDisc compatible recordable videodisc was available, invented by the original engineers from MCA DiscoVision who created the original LD/LV format. The discs were dye-based, like a CD-R or DVD-R - in fact, that's where CD-R and DVD-R technology comes from. The recordable LD was a pinkish-violet color. Ty Chamberlain (talk) 18:02, 18 July 2010 (UTC)
Can you play records on one of these things?
I know it sounds stupid, but it makes a fair amount of sense: records and laserdiscs are circular, spiral-recorded analog storage methods, and I knoew for a fact there are laser-turntables. So: Can I use my LD player for my LP discs? I know I could find out just by sticking one into the other, but I'm afraid I might break something.
Quick answer: No, you can't. Trying might not break anything, but I wouldn't think of it. Wyss 05:03, 5 Jun 2005 (UTC)
- I'm pulling this out of thin air, but a Laserdisc player's laser is presumably only capable of detecting whether there is a hole or not in its path; whereas with a vinyl record it is the shape of the V-groove that encodes the sound, and at the very least I imagine you'd need two lasers to determine the shape of each side of the groove, and you'd need to be a technical genius as well (waves hands). Science! -Ashley Pomeroy 21:54, 26 August 2005 (UTC)
- There are laser turntables that play vinyl records but any similarity ends there. :) Wyss 00:55, 27 August 2005 (UTC)
- You may have more luck with a CED player, since I think those actually read a groove like LPs...but, I think even with that you won't have any luck. -Gregg
- A CED player isn't capable of playing phonographic records (LPs) at all, since CED's similarities with LPs end with using a needle in the groove. CED has a vastly increased density of grooves on the disc, with 9,541 grooves per inch, compared with the LP's groove density from anywhere from 75 grooves/inch for old 78 RPM records, 300 grooves/inch for 33.3 RPM LPs, and 700 (IIRC) for 33.3 "microgroove" LPs. Plus, CED relies on capacitance differences picked up from the bottom of the groove (possibly done by vertical cutting of the grooves during mastering, or pits at the bottom of the groove) using a special electrode-fitted stylus, with no vibration of the stylus involved, while LPs solely rely on picking up mechanical vibration from the groove moving in both vertical and lateral directions, with a standard electrode-less phonographic stylus, with no capacitance involved. misternuvistor 19:57, 10 December 2005 (UTC)
- You may have more luck with a CED player, since I think those actually read a groove like LPs...but, I think even with that you won't have any luck. -Gregg
- I see this is an old question but a quick anecdote. I work for a school district and several years ago someone stole one of the LD players. Later, some dude brought it in a pawn shop and said it didn't work - and he was trying it with an LP! (The pawn shop gave it back to us.) 72.87.188.145 08:11, 10 October 2006 (UTC)