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My understanding was that regular VHS was recorded in Composite format, only S-VHS recorded the Y and C seperated. If VHS actually recorded the Y and C separately why didn't see s-video output on VCRs other than SVHS decks? Wasn't it JVC that made using a 4 Pin Mini DIN plug the standard for sending Y/C signals because S-VHS recorded the Y/C separately unlike VHS?

jamisonia wrote:

This is incorrect. Both VHS and S-VHS use a "color-under" recording process, in which the chrominance signal is downconverted in frequency (& reduced in bandwidth), then recorded as an AM signal, using the FM video carrier as bias. VHS does not have enough frequency response to record straight composite video in color. Its video frequency bandpass is 2.5 to 3 MHz, at best.

JVC introduced the S-Video connector to allow the user to get best results out of an S-VHS deck, which had a wider (luminance) video bandwidth & higher signal-to-noise ratio than standard VHS. It wasn't used on standard VHS VCRs because nobody really cared, & to encourage people to buy S-VHS VCRs (although that didn't work so well). Play back a VHS tape on an S-VHS machine, & the S-Video connector works as usual.

CED and VHD are color-under as well, right?

Out of curiosity, with these formats not being composite like LD, how would the Snell and Wilcox "moving orb" pattern look if it was used to test them? Would the cross-color artifacting be much less severe than that of Laserdisc? Or non-existant?

The frequencies chosen for the down-converted chrominance are identical for VHS and S-VHS at 627 kHz…

By making use of separate Y (luminance) and C (chrominance) inputs and outputs, it is possible to avoid some of the problems associated with separating encoded PAL signals prior to decoding. This technique is not, strictly speaking, related to the format, nor is it new, indeed there was a 1/2" color VCR system available in 1971 which was provided with separate Y/C outputs.

jamisonia wrote:

Not to beat a dead horse but I'm puzzled as to why no regular VCR ever provided s-video outputs then. Wouldn't it be easy to just the signal through to the s-video output instead of recombining the composite? Additionally did all of the DVD/VCR combos only allow s-video output to work on the DVD side? S-video was already there so why not hook it up? One more thing I was watching DVE the other day, and Joe Kane mentioned that VHS was a composite encoded source like laserdisc.

publius wrote:

jamisonia wrote:

The S-Video connector was kept (mostly) exclusive to S-VHS decks as a "prestige" feature to encourage people to buy them, & because the wider luminance bandwidth of S-VHS meant that the problems caused by the filtering showed up more easily. Also, as mentioned in my previous quote, there were non-S-VHS decks which had such an output. It just wasn't common.

Joe Kane to one side notwithstanding, if you want proof of my statement that luminance & chrominance are recorded separately on VHS, I can supply technical papers giving details.

publius wrote:

jamisonia wrote:

No no I believe you. It just seems very strange that more decks didn't have it, or that the DVD/VHS combo decks, that had s-video anyway wouldn't have supported it. I guess I will connect my S-VHS deck via s-video to watch to my few remaining VHS not on DVD tapes.

I have two JVC SVHS decks. I believe there some of the more recent decks though. Are there decks that have special picture controls and such? What are the best decks to play VHS tapes on? Honestly will it make a big difference in picture quality?

I currently have these SVHS decks

http://www.ebay.com/itm/JVC-HR-S3600-SU ... 3a6da48633

http://www.ebay.com/itm/JVC-HR-S5912-S- ... 1c21f17cd5

These are not my auctions, but only for picture purposes only. I picked both of these up at thrift stores. I have also seen quite a few of the black version of that silver one at thrift store, but it doesn't appear to have S-video input, only output. I assume these are basic level SVHS decks. I wasn't aware there were ones with any special features.

Correct me if I'm wrong, but if the information is encoded Y/C Separated why does it need a comb filter?

Author:	yazorin [ 27 Nov 2011, 04:03 ]
Post subject:	s video
i know with LD players composite plugs will actually look better then S video unless you have a really high end player, well is the same true for a tape player with S video? like an S VHS player?

Author:	publius [ 27 Nov 2011, 04:23 ]
Post subject:	Re: s video
No. Absolutely not. The whole reason for S-Video in the first place is that VHS & related tape formats are recorded with the luminance & chrominance separated, & recombining them only messes up the signal. So, a connector is provided which outputs the two signals separately. This is totally the reverse of LD, which is recorded with composite video, Y & C combined, & separating them has to be done carefully.

Author:	xtempo [ 27 Nov 2011, 14:11 ]
Post subject:	Re: s video
the best would be component or HDMI out on the more high end D-VHS players but VHS will still look like VHS compared to D-VHS but the picture does improve with component. can't say anything about HDMI wasn't lucky enough to find or buy one so I'm stuck with component which is a nice thing to be stuck with:)

Author:	Guest [ 30 Nov 2011, 18:15 ]
Post subject:	Re: s video
My understanding was that regular VHS was recorded in Composite format, only S-VHS recorded the Y and C seperated. If VHS actually recorded the Y and C separately why didn't see s-video output on VCRs other than SVHS decks? Wasn't it JVC that made using a 4 Pin Mini DIN plug the standard for sending Y/C signals because S-VHS recorded the Y/C separately unlike VHS?

Author:	publius [ 30 Nov 2011, 18:28 ]
Post subject:	Re: s video
jamisonia wrote: My understanding was that regular VHS was recorded in Composite format, only S-VHS recorded the Y and C seperated. If VHS actually recorded the Y and C separately why didn't see s-video output on VCRs other than SVHS decks? Wasn't it JVC that made using a 4 Pin Mini DIN plug the standard for sending Y/C signals because S-VHS recorded the Y/C separately unlike VHS? This is incorrect. Both VHS and S-VHS use a "color-under" recording process, in which the chrominance signal is downconverted in frequency (& reduced in bandwidth), then recorded as an AM signal, using the FM video carrier as bias. VHS does not have enough frequency response to record straight composite video in color. Its video frequency bandpass is 2.5 to 3 MHz, at best. JVC introduced the S-Video connector to allow the user to get best results out of an S-VHS deck, which had a wider (luminance) video bandwidth & higher signal-to-noise ratio than standard VHS. It wasn't used on standard VHS VCRs because nobody really cared, & to encourage people to buy S-VHS VCRs (although that didn't work so well). Play back a VHS tape on an S-VHS machine, & the S-Video connector works as usual.

LaserDisc Database https://forum.lddb.com/

s video https://forum.lddb.com/viewtopic.php?f=18&t=444	Page 1 of 2

Author:	elahrairrah [ 30 Nov 2011, 19:37 ]
Post subject:	Re: s video
publius wrote: jamisonia wrote: My understanding was that regular VHS was recorded in Composite format, only S-VHS recorded the Y and C seperated. If VHS actually recorded the Y and C separately why didn't see s-video output on VCRs other than SVHS decks? Wasn't it JVC that made using a 4 Pin Mini DIN plug the standard for sending Y/C signals because S-VHS recorded the Y/C separately unlike VHS? This is incorrect. Both VHS and S-VHS use a "color-under" recording process, in which the chrominance signal is downconverted in frequency (& reduced in bandwidth), then recorded as an AM signal, using the FM video carrier as bias. VHS does not have enough frequency response to record straight composite video in color. Its video frequency bandpass is 2.5 to 3 MHz, at best. JVC introduced the S-Video connector to allow the user to get best results out of an S-VHS deck, which had a wider (luminance) video bandwidth & higher signal-to-noise ratio than standard VHS. It wasn't used on standard VHS VCRs because nobody really cared, & to encourage people to buy S-VHS VCRs (although that didn't work so well). Play back a VHS tape on an S-VHS machine, & the S-Video connector works as usual. CED and VHD are color-under as well, right? Out of curiosity, with these formats not being composite like LD, how would the Snell and Wilcox "moving orb" pattern look if it was used to test them? Would the cross-color artifacting be much less severe than that of Laserdisc? Or non-existant?

Author:	publius [ 30 Nov 2011, 20:44 ]
Post subject:	Re: s video
elahrairrah wrote: CED and VHD are color-under as well, right? Out of curiosity, with these formats not being composite like LD, how would the Snell and Wilcox "moving orb" pattern look if it was used to test them? Would the cross-color artifacting be much less severe than that of Laserdisc? Or non-existant? Actually, CED & VHD use a "buried subcarrier" system. Essentially, this is a non-standard composite video signal, with a significantly lower subcarrier frequency (2.56 MHz for VHD, & the very low value of 1.53 MHz for CED). Rather severe comb-filtering is used to reduce interference between the luminance component & the subcarrier, so that the subcarrier can then be filtered out & heterodyned up to its proper frequency. As a result, cross-colour is significantly reduced, but at the expense of resolution. A similar, but gentler, process is used by the Faroudja Super-NTSC encoder, which I think was employed by WEA for mastering in the 1990s. It should be noted that both systems allow 500 kHz of chrominance bandwidth, also the maximum on VHS or S-VHS, as opposed to the 1.5 MHz (asymmetrical) of direct-composite recording on LD or broadcast tape. This was considered acceptable because many TVs used cheap chroma demodulators which would only make use of that much anyway. Also, here's a quote from a technical paper on S-VHS. R. M. Hartley, JVC Professional Products (UK) Ltd. wrote: The frequencies chosen for the down-converted chrominance are identical for VHS and S-VHS at 627 kHz… By making use of separate Y (luminance) and C (chrominance) inputs and outputs, it is possible to avoid some of the problems associated with separating encoded PAL signals prior to decoding. This technique is not, strictly speaking, related to the format, nor is it new, indeed there was a 1/2" color VCR system available in 1971 which was provided with separate Y/C outputs.

Author:	elahrairrah [ 30 Nov 2011, 21:40 ]
Post subject:	Re: s video
Oh yeah, I've seen monitors with separate Y/C inputs before S-Video came around (and should be compatible with S-Video if you get the right splitter cable.) The old Commodore64 monitors would be one: Interesting info about CED and VHD though. Always thought they were color under, but glad to know they were at least slightly better!

Author:	Guest [ 04 Dec 2011, 17:08 ]
Post subject:	Re: s video
publius wrote: jamisonia wrote: My understanding was that regular VHS was recorded in Composite format, only S-VHS recorded the Y and C seperated. If VHS actually recorded the Y and C separately why didn't see s-video output on VCRs other than SVHS decks? Wasn't it JVC that made using a 4 Pin Mini DIN plug the standard for sending Y/C signals because S-VHS recorded the Y/C separately unlike VHS? This is incorrect. Both VHS and S-VHS use a "color-under" recording process, in which the chrominance signal is downconverted in frequency (& reduced in bandwidth), then recorded as an AM signal, using the FM video carrier as bias. VHS does not have enough frequency response to record straight composite video in color. Its video frequency bandpass is 2.5 to 3 MHz, at best. JVC introduced the S-Video connector to allow the user to get best results out of an S-VHS deck, which had a wider (luminance) video bandwidth & higher signal-to-noise ratio than standard VHS. It wasn't used on standard VHS VCRs because nobody really cared, & to encourage people to buy S-VHS VCRs (although that didn't work so well). Play back a VHS tape on an S-VHS machine, & the S-Video connector works as usual. Not to beat a dead horse but I'm puzzled as to why no regular VCR ever provided s-video outputs then. Wouldn't it be easy to just the signal through to the s-video output instead of recombining the composite? Additionally did all of the DVD/VCR combos only allow s-video output to work on the DVD side? S-video was already there so why not hook it up? One more thing I was watching DVE the other day, and Joe Kane mentioned that VHS was a composite encoded source like laserdisc.

Author:	publius [ 05 Dec 2011, 00:41 ]
Post subject:	Re: s video
jamisonia wrote: Not to beat a dead horse but I'm puzzled as to why no regular VCR ever provided s-video outputs then. Wouldn't it be easy to just the signal through to the s-video output instead of recombining the composite? Additionally did all of the DVD/VCR combos only allow s-video output to work on the DVD side? S-video was already there so why not hook it up? One more thing I was watching DVE the other day, and Joe Kane mentioned that VHS was a composite encoded source like laserdisc. The S-Video connector was kept (mostly) exclusive to S-VHS decks as a "prestige" feature to encourage people to buy them, & because the wider luminance bandwidth of S-VHS meant that the problems caused by the filtering showed up more easily. Also, as mentioned in my previous quote, there were non-S-VHS decks which had such an output. It just wasn't common. Joe Kane to one side notwithstanding, if you want proof of my statement that luminance & chrominance are recorded separately on VHS, I can supply technical papers giving details.

Author:	elahrairrah [ 05 Dec 2011, 15:42 ]
Post subject:	Re: s video
jamisonia wrote: publius wrote: jamisonia wrote: Not to beat a dead horse but I'm puzzled as to why no regular VCR ever provided s-video outputs then. Wouldn't it be easy to just the signal through to the s-video output instead of recombining the composite? Additionally did all of the DVD/VCR combos only allow s-video output to work on the DVD side? S-video was already there so why not hook it up? One more thing I was watching DVE the other day, and Joe Kane mentioned that VHS was a composite encoded source like laserdisc. I believe some of the higher end Betamax VCRs included S-Video, but no VHS that wasn't S-VHS that I can recall did. Not even those odd "6 head" VCRs that were out there.

Author:	Guest [ 05 Dec 2011, 15:55 ]
Post subject:	Re: s video
publius wrote: jamisonia wrote: Not to beat a dead horse but I'm puzzled as to why no regular VCR ever provided s-video outputs then. Wouldn't it be easy to just the signal through to the s-video output instead of recombining the composite? Additionally did all of the DVD/VCR combos only allow s-video output to work on the DVD side? S-video was already there so why not hook it up? One more thing I was watching DVE the other day, and Joe Kane mentioned that VHS was a composite encoded source like laserdisc. The S-Video connector was kept (mostly) exclusive to S-VHS decks as a "prestige" feature to encourage people to buy them, & because the wider luminance bandwidth of S-VHS meant that the problems caused by the filtering showed up more easily. Also, as mentioned in my previous quote, there were non-S-VHS decks which had such an output. It just wasn't common. Joe Kane to one side notwithstanding, if you want proof of my statement that luminance & chrominance are recorded separately on VHS, I can supply technical papers giving details. No no I believe you. It just seems very strange that more decks didn't have it, or that the DVD/VHS combo decks, that had s-video anyway wouldn't have supported it. I guess I will connect my S-VHS deck via s-video to watch to my few remaining VHS not on DVD tapes.

Author:	yazorin [ 11 Dec 2011, 23:06 ]
Post subject:	Re: s video
jamisonia wrote: publius wrote: jamisonia wrote: Not to beat a dead horse but I'm puzzled as to why no regular VCR ever provided s-video outputs then. Wouldn't it be easy to just the signal through to the s-video output instead of recombining the composite? Additionally did all of the DVD/VCR combos only allow s-video output to work on the DVD side? S-video was already there so why not hook it up? One more thing I was watching DVE the other day, and Joe Kane mentioned that VHS was a composite encoded source like laserdisc. The S-Video connector was kept (mostly) exclusive to S-VHS decks as a "prestige" feature to encourage people to buy them, & because the wider luminance bandwidth of S-VHS meant that the problems caused by the filtering showed up more easily. Also, as mentioned in my previous quote, there were non-S-VHS decks which had such an output. It just wasn't common. Joe Kane to one side notwithstanding, if you want proof of my statement that luminance & chrominance are recorded separately on VHS, I can supply technical papers giving details. No no I believe you. It just seems very strange that more decks didn't have it, or that the DVD/VHS combo decks, that had s-video anyway wouldn't have supported it. I guess I will connect my S-VHS deck via s-video to watch to my few remaining VHS not on DVD tapes. those combo players are pure garbage and pretty much every vcr made in the last ten years is garbage, S VHS players are definitly the way to go. take a look at this beauty: http://soundt.18.forumer.com/a/jvc-hrs8 ... t5670.html

Author:	Guest [ 13 Dec 2011, 17:37 ]
Post subject:	Re: s video
I have two JVC SVHS decks. I believe there some of the more recent decks though. Are there decks that have special picture controls and such? What are the best decks to play VHS tapes on? Honestly will it make a big difference in picture quality?

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Author:	elahrairrah [ 13 Dec 2011, 17:59 ]
Post subject:	Re: s video
jamisonia wrote: I have two JVC SVHS decks. I believe there some of the more recent decks though. Are there decks that have special picture controls and such? What are the best decks to play VHS tapes on? Honestly will it make a big difference in picture quality? I have a JVC, a Mitsubishi and a Panasonic that is a rebadged JVC (I use the remote for my old JVC on the the Panny.) The Mitsu records better than the JVC or Panny (things I record in S-VHS on the Mitsu look flawless on the others, but when going from the JVC or Panny to the others I have tracking issues), but the Panny and JVC playback better as they have better TBCs. These are on the lower end of the S-VHS spectrum though (save for the Panny, as that has a 3D comb filter, so it's more of a mid-to-high-range VCR.) My friend had a pair of higher end Sony S-VHS VCRs that had jog/shuttle rings and a fancy GUI for tape dubbing. They cost him upwards of $1000 in the late 90s though, so you get what you pay for. Oh yeah, and one neat feature on the Mitsu that I really shouldn't use, but I do, is the super fast rewind and fast forward features. You can hear the thing switching gears as it goes into the faster mode! I really need to buy a rewinder so I don't wear out that motor or break a gear.

Author:	Guest [ 13 Dec 2011, 22:02 ]
Post subject:	Re: s video
I currently have these SVHS decks http://www.ebay.com/itm/JVC-HR-S3600-SU ... 3a6da48633 http://www.ebay.com/itm/JVC-HR-S5912-S- ... 1c21f17cd5 These are not my auctions, but only for picture purposes only. I picked both of these up at thrift stores. I have also seen quite a few of the black version of that silver one at thrift store, but it doesn't appear to have S-video input, only output. I assume these are basic level SVHS decks. I wasn't aware there were ones with any special features.

Author:	elahrairrah [ 13 Dec 2011, 22:41 ]
Post subject:	Re: s video
jamisonia wrote: I currently have these SVHS decks http://www.ebay.com/itm/JVC-HR-S3600-SU ... 3a6da48633 http://www.ebay.com/itm/JVC-HR-S5912-S- ... 1c21f17cd5 These are not my auctions, but only for picture purposes only. I picked both of these up at thrift stores. I have also seen quite a few of the black version of that silver one at thrift store, but it doesn't appear to have S-video input, only output. I assume these are basic level SVHS decks. I wasn't aware there were ones with any special features. The 3600 is a lower end deck. The 5912 is a middle range deck. Like most model numbering the higher number after the S in the JVC names denotes the higher end of the deck. So the best JVC decks are the HR-S7xxx and HR-S9xxx decks. Both of those lines of VCRs have 3D comb filters and good TBCs, but the 9xxx series has more memory for the TBC. I imagine the comb filters in the 3xxx and 5xxx are 2D.

Author:	Guest [ 13 Dec 2011, 23:08 ]
Post subject:	Re: s video
Correct me if I'm wrong, but if the information is encoded Y/C Separated why does it need a comb filter? How much better do these higher end VCRs make commercial VHS tapes look? How about the DVHS decks? Do they have these bells and whistles for regular VHS watching?

Author:	elahrairrah [ 13 Dec 2011, 23:12 ]
Post subject:	Re: s video
jamisonia wrote: Correct me if I'm wrong, but if the information is encoded Y/C Separated why does it need a comb filter? TV signals still get cross-color and cross-luminance artifacting (which is why there was coined the term "the Ebert Effect" in regards to cross-color as the ties he wore on his movie review show "At the Movies" often gave off the artifacting.) So it would help in cleaning up TV signals (and whatever else you fed into it--like an LD perhaps?) for recording purposes or just to feed a better picture to your TV.

Author:	Guest [ 13 Dec 2011, 23:14 ]
Post subject:	Re: s video
Okay that makes sense, so its just going to improve recording, not playback?