VHS "LP" mode
Lauren Weinstein
tape speeds? Original machines presumably had SP and LP modes.
Later EP mode appeared. Newer machines seem to have SP and EP, but
while most can play back LP tapes, they no longer can record them.
This seems like an odd development cycle, given that in the Beta
world, the equivalent "obsolete" speed was the original (fastest)
Beta 1, which better machines can now play back but not record. The
question is, why would an "intermediate" VHS speed have become
seemingly obsolete? Was it found in practice to be insufficiently
better than EP in the consumer world? Or was it just assumed that
the masses recording football games wouldn't notice the quality
difference anyway, and were just shooting for the longest possible
record time, so why bother including LP record capabilities?
Do any newer consumer machines include LP record capabilities?
The S-VHS machines I've seen all seem to be in the "we'll play
back LP but won't record it" category. Is LP completely obsolete?
Thanks.
--Lauren--
P.S. I freely admit that (until recently) I have avoided VHS since
its inception, sticking with UMATIC and Beta for my own purposes.
But the force of numbers has pushed me to add in an S-VHS machine.
It's really too bad SONY fouled up the marketing so badly on Beta
in the beginning.
--LW--
J. Eric Townsend
>Later EP mode appeared. Newer machines seem to have SP and EP, but
>while most can play back LP tapes, they no longer can record them.
I think you should change that "most" to "few". My Toshiba MT-80
played LP (but the head cracked, and I'm afraid to get an estimate for
replacement). My JVC-S8000U will *not* play LP. It had a list price
of $1500 and can't deal with LP! I didn't discover this until I bought
"Punk Rock Movie", which was released in LP. (My JVC unit
tries to play it as S-VHS, so you get a screwed picture but ok
sound.)
Anyone that specs a new VCR design and leaves out LP should be taken out
and shot... :-(
umount ~jet/soapbox
--
J. Eric Townsend Internet: j...@uh.edu Bitnet: jet@UHOU
Systems Manager - University of Houston Dept. of Mathematics - (713) 749-2120
EastEnders list: east...@karazm.math.uh.edu
Skate UNIX(r)
Mark Newton John
About Sony and the marketing of Beta, Sony started out very well in
the beginning. There was a time that all VCRs were called
Betamaxes, similar that most bandages are called Band-Aids, cola
drinks Coke, and tissues Kleenex.
The problems (in hindsight) were relatively minor. To keep the
cassette smaller, and at the current record speed, you only got one
hour of record time. a problem for the American market, but then
again, just use two tapes... Morita did not want a cassette the
size of what VHS was to become. So, Sony engineered Beta II. Tow
hours.
The one thing that Sony could not overcome was the power of RCA.
SOny had the reputation of their studio and televisions, they did
not want to give away the VCR to them. So RCA went to JVC and
slowly dominated the home VCR market. No matter that Beta was
technologically better, VHS had a leg up on Beta, because RCA was
the largest company in home video sales in the 70's and 80's.
Sony could not control software, and when faced witht he prospect
in carrying duplicate inventory, primordial tape rental places
carried the format for what there were more machines. No matter
that Sony developed AFM HiFi, a high-band recording for improved
picture, VHS was more popular. Call it herd mentality.
Anyway, Sony has learned from all of this, it now owns a studio and
record company, and through it's 8mm camcorder (virtually a
mini-Beta), Sony is taking the camcorder market from VHS.
Beta will still be around, afterall, there are still a sizable
amount of machines out there, not to mention the home market. Sony
continues to develop new Beta VCRs, such as the top-line SL-2100
and EDV-9500 machines.
Mata ne da-cha
--
the good guys! Sakura-mendo, CA
Internet: mfo...@sactoh0.SAC.CA.US
H. Morrow Long
|> This seems like an odd development cycle, given that in the Beta
|> world, the equivalent "obsolete" speed was the original (fastest)
|> Beta 1, which better machines can now play back but not record. The
|> question is, why would an "intermediate" VHS speed have become
|> seemingly obsolete? Was it found in practice to be insufficiently
|> better than EP in the consumer world? Or was it just assumed that
|> the masses recording football games wouldn't notice the quality
|> difference anyway, and were just shooting for the longest possible
|> record time, so why bother including LP record capabilities?
|>
|> Do any newer consumer machines include LP record capabilities?
|> The S-VHS machines I've seen all seem to be in the "we'll play
|> back LP but won't record it" category. Is LP completely obsolete?
|> Thanks.
|>
|> --Lauren--
This is a FAQ (Frequently Asked Question. Is anyone in this newsgroup
keeping a MFAQ and Answer list up? Otherwise I may consider doing so.
As Lauren is a respected long-time member of Usenet (I remember his
Stargate work from many years ago) and a VHS neophyte I will post an
answer to 2 FAQ answers here:
1. "What is the story behind LP mode?"
Before EP (sometimes called SLP) was invented by JVC some
manufacturers created a mode that was twice the playing time
of SP. It was never blessed by JVC (the VHS standards keeper) -
and they superceded it with EP (which has 3 times the playing time
of SP).
Some posters have remarked that to support multiple playing
speeds properly dictates additional heads. Therefore 4 head
players are better at displaying EP mode tapes. An additional
set of heads would be useful to support LP mode in a proficient
manner. I would be interested in knowing if this is true.
2. Do any newer consumer machines include LP record capabilities?
Is LP completely obsolete?
Many VHS machines still do (my Samsung has all 3 recording speeds).
But I haven't seen a SVHS machine that records in it
(my JVC HRS-5000U supports playing VHS LP mode tapes).
I would be interested in knowing if any machine support LP
recording in SVHS mode (!!!). I assume most manufacturers think
this would be a silly idea (if you are going to spend the money
for SVHS why not go for all of the quality you can get with the
format - actually SVHS EP mode is pretty good, comparable to
good VHS, this way I have all of the Twin Peaks episodes on 3
SVHS cassettes rather than 10).
The VHS and SVHS standards supported by JVC do not include LP.
--
H. Morrow Long
Manager of Development
Yale Univ. Comp Sci Dept. Computing Facility
Mail Stop 2158, UUCP: yale!Long-Morrow
Yale Station, ARPA: Long-...@CS.Yale.EDU
New Haven, CT 06520 BITNET: Long-...@YaleCS.BITNET
(203)-432-1254 FAX: (203)-432-0593
Mark Newton John
> In article <9011210050.0.UUL1.3#1...@vortex.COM> lau...@vortex.COM (Lauren Weinstein) writes:
> >Later EP mode appeared. Newer machines seem to have SP and EP, but
> >while most can play back LP tapes, they no longer can record them.
>
> I think you should change that "most" to "few". My Toshiba MT-80
> played LP (but the head cracked, and I'm afraid to get an estimate for
> replacement). My JVC-S8000U will *not* play LP. It had a list price
> of $1500 and can't deal with LP! I didn't discover this until I bought
> "Punk Rock Movie", which was released in LP. (My JVC unit
> tries to play it as S-VHS, so you get a screwed picture but ok
> sound.)
>
> Anyone that specs a new VCR design and leaves out LP should be taken out
> and shot... :-(
>
Shot eh? Hmm. I cannot believe why ANYONE would want LP. Especially
in any new machines. The *only* reason current machiones even play
the speed is because of old LP recorded material.
From the start, LP was a hack. Just reduce the tape speed
(essentially) and double the record time. The problem is that the
heads aren't designed to do LP well, unless you tack on another set
of heads on the drum. JVC *NEVER* sanctioned the LP speed, that is
a reason that no JVC will record, much less play back LP. LP
playback on JVC and Zenith clones is just that, playback. Forget
scanning and freeze frame... Even with their best machines.
Record quality between LP and EP (SLP) is almost unnoticeable.
(read bad) and it is a smaller compromise to design a head for
SP/EP than it is to deal with LP. Sure sure, Matsushita has all
three speeds, but that's only Matsushita. All other major
manufacturers (Sony, Hitachi, Sharp, Mitsubishi, et al) leave out
LP. Well, I think RCA makes Hitachi include LP on VCRs sold under
the RCA name...
There is really only one speed to record, and that is SP. Unless
you are trying to fit five minutes of a 125 minute movie onto one
tape, or you tape late night movies (to scan faster through the
commercials), the slower tape speeds give you less than
satisfactory results.
Ja ne da-cha
Alan Larson
>In article <9011210050.0.UUL1.3#1...@vortex.COM> lau...@vortex.COM (Lauren Weinstein) writes:
>>tape speeds? Original machines presumably had SP and LP modes.
>>Later EP mode appeared. Newer machines seem to have SP and EP, but
>>while most can play back LP tapes, they no longer can record them.
>
>The main reason for using LP instead EP was that the linear audio
>track sounded better at the higher speed. The quality of the
>helical track (video and HiFi) is pretty much the same at either speed.
Apparently, you are using a different machine from either of mine.
On both my machines (an old Panasonic, and not so old Mitsubishi, both
4 head), LP picture quality is almost as good as SP. LP comes much
closer to SP than to EP in quality.
>(The reason SP looks better then both LP and EP is that a different
>set of heads is used for SP.) Newer HiFi decks seem to regard LP
>as a waste of tape. If you're going to sacrifice quality you might
>as well use EP and at least benifit from longer playing times.
The problem is that LP lets us get good quality and somewhat longer
playing times. Unfortunately, I am beginning to suspect that the
LP tapes degrade in quality to about the same as yesterday's EP
tapes after a few months. Strange. Even so, for timeshifting,
LP has great advantages.
Alan
Alan Larson
>Anyway, Sony has learned from all of this, it now owns a studio and
>record company, and through it's 8mm camcorder (virtually a
>mini-Beta), Sony is taking the camcorder market from VHS.
On inspection of the 8mm tape loading process, it looks more like
VHS than Beta to me. Looks like the M load, not the U-load of the
Beta systems.
Had they used all the tape width for the video, instead of the
mostly unused PCM audio tracks and linear audio and control tracks,
8mm could have had much better performance. As is, its resolution
is slightly behind plain VHS. The signal/noise and gray scale
results look slightly better, though.
Alan
William R. Cruce
See below
>[...]
>Record quality between LP and EP (SLP) is almost unnoticeable.
>[...] Sure sure, Matsushita has all
>three speeds, but that's only Matsushita.
Matsushita managed to do it right. At least all the Panasonic VCRs
I've used were able to record and play back LP speed that was MOST
VERY NOTICEABLY BETTER than EP speed. Yes, it was worse than SP.
And you couldn't get clean special effects (noise bars on freeze
frame, fast forward, etc.)
>[...]
>There is really only one speed to record, and that is SP. Unless
>you are trying to fit five minutes of a 125 minute movie onto one
>tape, ...
EXACTLY. If you want to tape a movie which is over about 124 minutes
(most T120 tapes have about 4 mins extra) but you don't want to go to
the BAD quality picture of EP. There are quite a few movies that
are 130-140m long and a goodly number out to 180m. One of the best
things about BETA is that at the BII speed you have 180m. There is
a growing trend to produce cassettes that hold 130min at SP (with
standard tape I think). The T160s are, I think, only made by BASF and
use a thinner tape which wears and jams more easily.
One other alternative, now appearing on at least Mitsubishi VHS machines
is the ability to tell the machine to use as much tape as possible at
SP and then do the remainder at EP. For movies that are just a tad
longer than a T120 will hold, you end up with mostly credits at the
slow speed.
Still, on my old Panasonic I could just record at LP and get a good
compromise between picture and time.
--
-------------------------------------------------------------------------
"All those moments will be lost, in time, like tears in rain." -Roy Batty
Bill Cruce Internet: wl...@uhura.neoucom.edu
N.E. Ohio U. College of Medicine Rootstown, Ohio 44272
Jon Rosen
>In article <9011210050.0.UUL1.3#1...@vortex.COM> lau...@vortex.COM (Lauren Weinstein) writes:
><tape speeds? Original machines presumably had SP and LP modes.
><Later EP mode appeared. Newer machines seem to have SP and EP, but
><while most can play back LP tapes, they no longer can record them.
>
>people who licensed machines get away with adding the LP speed. I don't
>remember if RCA forced it in or not, but JVC never officially sanctioned the
>LP speed. JVC did put its backing behind the EP (SLP) speed though.
>
>So, all JVC built decks will record SP and EP, and play back SP, LP and EP.
>Even though JVC will play back the LP speed, a majority (if not all) of its
>machines will not give you many of the special effects modes in LP.
>
>Personal opinion: don't record anything in the LP speed, that you are going
> to keep. You may find that you won't be able to play it very well
> on any new machine that you purchase.
As I remember the technology from the early 80's, the LP mode was
managed simply by reducing the tape speed. While this did not
directly effect S/N ratio because the head-to-tape speed does not
vary in a helical scan recorder regardless of the horizontal tape
speed (unlike audio tape with fixed heads where varying tape speed
directly effects the signal), slowing the tape did have the effect
of overlapped video signals:
SP / / / / / / / /
LP ////////////////
Thus there was distortion introduced in LP mode.
ELP (later just EP) was introduced by JVC using two heads that were
phased differently:
EP /\/\/\/\/\/\/\/\
Using this technique, the tape could be slowed even further (hence
6 hours instead of 2 or 4) but because the alternating head signals
were out of phase with each other, there was significantly less
distortion, i.e., a better picture. Of course, early VHS EP still
had the problem of even slower tape speed on the linear audio track
so audio response suffered... This is why I always found, in the
early days anyway, that my EP recordings were visually better than
my LP and so I dropped LP entirely... If I wanted quality, I always
went with SP, but if I wanted length, I went with EP... This is
still pretty much the way things are today... In addition, since a
a set of heads is necessary for special effects in each speed (with
the heads geared specifically to the speed and phase of the signals
for that tape speed), two head recorders can usually only do
effects in EP (the most commonly used speed unfortunately) and four
head recorders can usually only do EP or SP (LP is once again
ignored)... (Please excuse any minor technical inaccuracies... this
is a layman's description of a technical subject as it has been
explained to me by electronic wizards... If there is a major error,
please feel free to correct it on-line, but no flames, please...)
Jon Rosen
Vidiot
<tape speeds? Original machines presumably had SP and LP modes.
<Later EP mode appeared. Newer machines seem to have SP and EP, but
<while most can play back LP tapes, they no longer can record them.
First there was SP, as defined by JVC, the VHS license holder. They let the
people who licensed machines get away with adding the LP speed. I don't
remember if RCA forced it in or not, but JVC never officially sanctioned the
LP speed. JVC did put its backing behind the EP (SLP) speed though.
So, all JVC built decks will record SP and EP, and play back SP, LP and EP.
Even though JVC will play back the LP speed, a majority (if not all) of its
machines will not give you many of the special effects modes in LP.
The S-VHS machines that are out there are controlled by JVC this time around,
which is why LP is not there to record with.
Personal opinion: don't record anything in the LP speed, that you are going
to keep. You may find that you won't be able to play it very well
on any new machine that you purchase.
--
harvard\ att!nicmad\ spool.cs.wisc.edu!astroatc!vidiot!brown
Vidiot ucbvax!uwvax..........!astroatc!vidiot!brown
rutgers/ decvax!nicmad/ INET:<@spool.cs.wisc.edu,@astroatc:brown@vidiot>
Joel B Levin
>three speeds, but that's only Matsushita. All other major
>manufacturers (Sony, Hitachi, Sharp, Mitsubishi, et al) leave out
>LP. Well, I think RCA makes Hitachi include LP on VCRs sold under
>the RCA name...
My six year old Montgomery Wards (Sharp) plays and records all three
speeds. And "only" Matsushita covers a lot of nameplates (including
my other machine, a Sylvania-Phillips).
/JBL
=
Nets: le...@bbn.com | "There were sweetheart roses on Yancey Wilmerding's
or {...}!bbn!levin | bureau that morning. Wide-eyed and distraught, she
POTS: (617)873-3463 | stood with all her faculties rooted to the floor."
Bill Vermillion
>
> SP / / / / / / / /
> LP ////////////////
>
>Thus there was distortion introduced in LP mode.
>
>ELP (later just EP) was introduced by JVC using two heads that were
>phased differently:
>
> EP /\/\/\/\/\/\/\/\
>
Well, what you described is what Sony first introduced when the brought out
the first home VCR and called it a BetaMax.
The changed azimuth (not phase) was what made it possilbe to put so much on
such a litte tape. The EP speed called for narrower heads to get a decent
signal to noise ratio, among other things.
--
Bill Vermillion - UUCP: uunet!tarpit!bilver!bill
: bi...@bilver.UUCP
Steven V Fenger
>>tape, ...
>
>EXACTLY. If you want to tape a movie which is over about 124 minutes
>(most T120 tapes have about 4 mins extra) but you don't want to go to
>the BAD quality picture of EP. There are quite a few movies that
>are 130-140m long and a goodly number out to 180m. One of the best
>things about BETA is that at the BII speed you have 180m. There is
>a growing trend to produce cassettes that hold 130min at SP (with
>standard tape I think). The T160s are, I think, only made by BASF and
>use a thinner tape which wears and jams more easily.
>
the picture in the ad the new BASF tape comes in a bright yellow box.
Steven Fenger
fen...@buster.cps.msu.edu
fen...@frith.egr.msu.edu
Vidiot
<In article <9011210050.0.UUL1.3#1...@vortex.COM> lau...@vortex.COM (Lauren Weinstein) writes:
<>Later EP mode appeared. Newer machines seem to have SP and EP, but
<>while most can play back LP tapes, they no longer can record them.
<
<I think you should change that "most" to "few". My Toshiba MT-80
<played LP (but the head cracked, and I'm afraid to get an estimate for
<replacement). My JVC-S8000U will *not* play LP. It had a list price
<of $1500 and can't deal with LP! I didn't discover this until I bought
<"Punk Rock Movie", which was released in LP. (My JVC unit
<tries to play it as S-VHS, so you get a screwed picture but ok
<sound.)
There is something wrong with your HR-S8000U, as mine play LP speed. The manual
even says that it will be detected and played. All JVC VCRs will play LP.
Since you get OK sound, that means it is playing at the correct speed. Maybe
there is something wrong with the tape. Did you try playing it on a different
machine? Otherwise the JVC deck needs to be checked out.
Michael Bender
>Oh, and one more thing. 8mm does not have a control track. Unlike
>1/2" consumer, 8mm does not need it.
How does it keep the transport sync then? Does it regenerate sync and servo
control pulses from the video data?
mike
--
Won't look like rain, Won't look like snow, | DOD #000007
Won't look like fog, That's all we know! | AMA #511250
We just can't tell you anymore, We've never made oobleck before! | MSC #298726
Richard Karlquist
> And of course, on the top line 8mm VCRs, you have multitrack PCM,
> up to 24 hours of audio on one tape. To stave off you detractors,
> so what that 8mm PCM only goes up to 15kHz. Most of you guys can't
> hear that high anyway, and besides, 90% of the consumer cassette
> (analog) decks can't record higher that about 15kHz anyway.
>
> the good guys! Sakura-mendo, CA
Granted the 15 kHz. bandwidth of PCM is not a severe limitation.
However, you didn't mention that the quantization is only 8 bits,
with companding to give the illusion that the dynamic range is
more than 50 dB. Of course the drawback is the noise modulation,
pumping and other companding artifacts.
Rick Karlquist
Jack_Waho...@cup.portal.com
neophyte in the field of video. On Prodigy, I noticed an ad for a
Sharp 4-head Stereo Hi-Fi VCR (Model VCM705V) for $299. Is this a
decent price for this deck? At first glance it appears reasonable to
me, but I have no knowledge of its performance capabilities or service
track record. All I know is that it's little more than half what I
paid for my Mitsubshi M-50 over a year ago. Netland, your advice is
welcomed, and gawd knows I need it. Danke!
One more quickie... have heard VCR's make decent audio tape decks even
on EP. True or BS? Thanks, again.
Jack Pettrey
Severna Park, Md (just moved from Lockport, NY)
Alan Larson
>> 8mm could have had much better performance. As is, its resolution
>> is slightly behind plain VHS. The signal/noise and gray scale
>> results look slightly better, though.
>>
>> Alan
>
>Uh sorry, no way. 8mm is better than VHS in video quality. Just
>looking at the technical specifications of 8mm, it can record more
>information than VHS can. Sorry, but you are wrong on the point
>that VHS is better than 8mm in resolution.
Most manufacturers do not publish real technical specs.
>I mean, I think you should comment on subjects that you know about.
Thank you. I have been doing exactly that. If you wish to argue
about credentials, we can do it via mail.
>8mm does NOT have linear audio, it has AFM mono, using the video
>heads to lay down video and audio, a la Beta HiFi. Instead of the
>now pathetic audio performance of linear audio, the AFM of 8mm is
>20-20kHz.
The assignments of the tracks on the tape width have been published
here and in other places. There are linear audio tracks assigned on
8mm tape. They are not used by any consumer equipment.
Alan
William Kucharski
>Record quality between LP and EP (SLP) is almost unnoticeable.
>(read bad) and it is a smaller compromise to design a head for
>SP/EP than it is to deal with LP. Sure sure, Matsushita has all
>three speeds, but that's only Matsushita. All other major
>manufacturers (Sony, Hitachi, Sharp, Mitsubishi, et al) leave out
>LP. Well, I think RCA makes Hitachi include LP on VCRs sold under
>the RCA name...
Well, let me throw in my $.02 on the issue. I've an old (circa 1984) VHS model
with "all three" speeds, and the quality of recording definitely goes SP-LP-EP,
with LP mode about half way between SP and EP. One other benefit is that since
it's non-HiFi, tapes made in LP mode sound worse than SP but much better than
EP.
>There is really only one speed to record, and that is SP. Unless
>you are trying to fit five minutes of a 125 minute movie onto one
>tape, or you tape late night movies (to scan faster through the
>commercials), the slower tape speeds give you less than
>satisfactory results.
OK -- Please get me "The Sound of Music" on one SP tape. Don't have a T-180
in stock? Sometimes compromises have to be made for the sake of convenience,
and in a non-HiFi world a compromise to LP beats a compromise to EP by leaps
and bounds...
BTW, I don't use the old VCR much any more as I have a vintage 1988 Mitsubishi
VHS HiFi, but I'm just trying to make a point from the (unfortunately) point of
view of the average consumer -- you know, the kind of person who hates
letterboxing (only .5 :-) )...
--
| William Kucharski, Solbourne Computer, Inc. | Opinions expressed above
| Internet: kuch...@Solbourne.COM | are MINE alone, not those
| uucp: ...!{boulder,sun,uunet}!stan!kucharsk | of Solbourne...
| Snail Mail: 1900 Pike Road, Longmont, CO 80501 | "It's Night 9 with D2 Dave"
Mark Newton John
> In article <44...@sactoh0.SAC.CA.US> mfo...@sactoh0.SAC.CA.US (Mark Newton John) writes:
> >Oh, and one more thing. 8mm does not have a control track. Unlike
> >1/2" consumer, 8mm does not need it.
>
> How does it keep the transport sync then? Does it regenerate sync and servo
> control pulses from the video data?
Well..... I dunno. Unfortunately, I do not have my reference
materials handy, but 8mm has an auto track finding capability.
If I find it, I'll have to post it. Sorry to give an incomplete
reply, but how 8mm manages sync, etc. is one of the things that
does not have reserved brain memory. heh heh.
sna...@yahoo.com
that will play LP mode tapes really well. I am converting my LP tapes
them to dvd with my pioneer dvd recorder, but there are lots of hiss
and pops coming the speaker on the tv. I've tried a panasonic dvd
recorder/vcr combo, and the hiss and pops were virtually eliminated. I
don't have that unit anymore, and i assume the lack of hiss and pops
were due to added technology so the conversion could be a good one.
It's weird that most vcr's made these days won't even record an LP
tape, but will play one. Though with my vcr and one other i've tried,
the hiss and pops are there. :(