VideoHelp Forum

Our website is made possible by displaying online advertisements to our visitors. Consider supporting us by disable your adblocker or try DVDFab and copy, convert or make Blu-rays and DVDs! :)
+ Reply to Thread
Results 1 to 19 of 19
Thread
  1. I'm trying to find a linear stereo commercial tape, not hi-fi stereo. What kind of indicator should I look for on the tape/packaging? Is there a list of linear stereo commercial tapes?
    Image Attached Thumbnails Click image for larger version

Name:	linear stereo.jpg
Views:	42
Size:	333.5 KB
ID:	46413  

    Quote Quote  
  2. On your pic there is right next to the VHS logo "HI-FI STEREO"
    Quote Quote  
  3. Yes but it also says Dolby on linear tracks, so does it mean it has both linear and hifi stereo?
    Quote Quote  
  4. Member DB83's Avatar
    Join Date
    Jul 2007
    Location
    United Kingdom
    Search Comp PM
    Pardon my ignorance but what is the difference between linear stereo and plain ol' stereo.

    I have just plucked 3 tapes of a shelf and they read:

    Stereo - Mono Compatable
    Hi-Fi Stereo - Digitally remastered
    Dolby Stereo

    Go figure
    Quote Quote  
  5. I am a digital guy, but for VHS I know, at least think, that the "linear stereo" is at the place where the linear mono is placed.

    Why do you want or need "Linear Stereo", instead of "HI-FI Stereo", just to learn about VHS tech.
    Quote Quote  
  6. yeah just for collecting purposes and I have a machine that can play such tapes.
    Quote Quote  
  7. Originally Posted by digicube View Post
    Yes but it also says Dolby on linear tracks, so does it mean it has both linear and hifi stereo?
    Probably yes, only linear stereo require Dolby processor to recover normal audio (i assume common Dolby B system was used on those tapes).
    Quote Quote  
  8. Member
    Join Date
    Jul 2007
    Location
    United States
    Search Comp PM
    Being a Betaphile, I remember the envy of seeing linear stereo sound on VHS tapes, then breathing a huge sigh of relief and a hearty laugh when Beta Hi-Fi debuted, completely blowing away VHS stereo. Of course, the VHS camp countered with VHS Hi-Fi, but at least Beta was first!

    Note the very limited range and poor S/N ratio of VHS linear stereo below.

    From Wikipedia:

    "Original linear audio system[edit]

    In the original VHS specification, audio was recorded as baseband in a single linear track, at the upper edge of the tape, similar to how an audio compact cassette operates. The recorded frequency range was dependent on the linear tape speed. For the VHS SP mode, which already uses a lower tape speed than the compact cassette, this resulted in a mediocre frequency response of roughly 100 Hz to 10 kHz for NTSC;[citation needed] frequency response for PAL VHS with its lower standard tape speed was somewhat worse. The signal-to-noise ratio (SNR) was an acceptable 42 dB. Both parameters degraded significantly with VHS's longer play modes, with EP/NTSC frequency response peaking at 4 kHz.

    Audio cannot be recorded on a VHS tape without recording a video signal, even in the audio dubbing mode. If there is no video signal to the VCR input, most VCRs will record black video as well as generate a control track while the audio is being recorded. Some early VCRs would record audio without a control track signal, but this was of little practical use since the absence of a control track signal meant that the linear tape speed was irregular during playback.

    More expensive decks offered stereo audio recording and playback. Linear stereo, as it was called, fit two independent channels in the same space as the original mono audiotrack. While this approach preserved acceptable backward compatibility with monoaural audio heads, the splitting of the audio track degraded the signal's SNR to the point that audible tape hiss was objectionable at normal listening volume. To counteract tape hiss, decks applied Dolby B noise reduction for recording and playback. Dolby B dynamically boosts the mid-frequency band of the audio program on the recorded medium, improving its signal strength relative to the tape's background noise floor, then attenuates the mid-band during playback. Dolby B is not a transparent process, and Dolby-encoded program material will exhibit an unnatural mid-range emphasis when played on non-Dolby capable VCRs.

    High-end consumer recorders took advantage of the linear nature of the audio track, as the audio track could be erased and recorded without disturbing the video portion of the recorded signal. Hence, "audio dubbing" and "video dubbing", where either the audio or video are re-recorded on tape (without disturbing the other), were supported features on prosumer linear video editing-decks. Without dubbing capability, an audio or video edit could not be done in-place on master cassette, and requires the editing output be captured to another tape, incurring generational loss.

    Studio film releases began to emerge with linear stereo audiotracks in 1982. From that point onward nearly every home video release by Hollywood featured a Dolby-encoded linear stereo audiotrack. However, linear stereo was never popular with equipment makers or consumers."
    Quote Quote  
  9. Member
    Join Date
    Aug 2010
    Location
    San Francisco, California
    Search PM
    Originally Posted by DB83 View Post
    Pardon my ignorance but what is the difference between linear stereo and plain ol' stereo.

    I have just plucked 3 tapes of a shelf and they read:

    Stereo - Mono Compatable
    Hi-Fi Stereo - Digitally remastered
    Dolby Stereo

    Go figure
    The first is a pair of linear audio tracks along the edge of the tape. A mono deck will combine both tracks by reading them with the same head.
    The second is a series of helically-scanned tracks picked up by AFM heads on the video drum.
    The third is the same as the first with Dolby noise reduction.
    Quote Quote  
  10. Originally Posted by DB83 View Post
    Pardon my ignorance but what is the difference between linear stereo and plain ol' stereo.

    I have just plucked 3 tapes of a shelf and they read:

    Stereo - Mono Compatable
    Hi-Fi Stereo - Digitally remastered
    Dolby Stereo

    Go figure
    The linear track can be mono or stereo. The linear track is recorded linearly (just like a cassette) along the side of the tape. It has a low bandwidth, especially with slower tape speeds. The Hi-Fi track is recorded by the helical scan heads, next to the video tracks. This page has a picture:

    http://videosuite.blogspot.com/2007/05/picture-but-no-sound.html

    Name:  vhs tracks.jpg
Views: 161
Size:  29.3 KB

    A is the linear track(s), D is the hi-fi track. All tapes must include a linear track, and all players must be able to play the linear track. If the linear track is stereo it can be encoded with Dobly Pro Logic surround sound.
    Last edited by jagabo; 8th Aug 2018 at 22:13.
    Quote Quote  
  11. Member
    Join Date
    Jul 2007
    Location
    United States
    Search Comp PM
    As I recall, there were issues playback of stereo tracks on mono VCRs, particularly crosstalk between channels. Understandable given the small width given to the audio track.
    Quote Quote  
  12. There should be 100 percent crosstalk when playing a stereo linear track with a mono player. Ie, it should be a 50:50 mix. The problem would be when the playback head is mis-aligned and you get an uneven mix.
    Quote Quote  
  13. I believe this picture is not entirely correct - HiFi track may use different angle (so audio track will be not parallel to video) and it use different spectrum (thus provide frequency separation) - VCR record B/W signal (except linear audio) - all signals (except linear audio) are converted to FM but they are located in non overlapping (from spectrum perspective) zones - HiFi audio occupy spectrum before chrominance and chrominance before luminance - as HiFi FM has lowest frequency thus it can penetrate tape deeper than for example chrominance and especially luminance signals.
    Quote Quote  
  14. Member
    Join Date
    Aug 2010
    Location
    San Francisco, California
    Search PM
    In VHS Hi-Fi, FM audio is placed between chrominance and luminance bands. Audio tracks are perfectly parallel to video tracks; they have to be, since the heads are on the same circle. Audio tracks are recorded deeper into the oxide and video tracks are recorded on top of them. The "different angle" is head azimuth, which makes the appropriate signal stronger for the appropriate playback head. FM capture effect does the rest.
    Quote Quote  
  15. Originally Posted by JVRaines View Post
    In VHS Hi-Fi, FM audio is placed between chrominance and luminance bands. Audio tracks are perfectly parallel to video tracks; they have to be, since the heads are on the same circle. Audio tracks are recorded deeper into the oxide and video tracks are recorded on top of them. The "different angle" is head azimuth, which makes the appropriate signal stronger for the appropriate playback head. FM capture effect does the rest.
    True - my fault.
    Quote Quote  
  16. Member
    Join Date
    Mar 2011
    Location
    Nova Scotia, Canada
    Search Comp PM
    All "linear" means as far as VHS goes is that it's not VHS HiFi, which is helically recorded like the video and actually was quite good except the mfr's usually put non defeatable peak limiters in. Linear just means standard AM radio quality audio and I suspect it's another one of those stupid marketing names.
    Quote Quote  
  17. Member Cornucopia's Avatar
    Join Date
    Oct 2001
    Location
    Deep in the Heart of Texas
    Search PM
    No, jagabo was correct: the non-hifi audio head(s) are stationary (not rotating - the video & hifi heads do that), so when the tape passes by LINEARLY, it gets recorded, linearly, along the top edge. (Bottom edge has control track).

    Scott
    Quote Quote  
  18. Member
    Join Date
    Aug 2010
    Location
    San Francisco, California
    Search PM
    And here is what the linear audio head assembly looks like (center of picture). It's about the same as any other stationary tape head. The control track head is built into the same housing.
    Quote Quote  
  19. Member dellsam34's Avatar
    Join Date
    Jan 2016
    Location
    Paris Ca, 92345 Mexico
    Search PM
    As far as I know VCR's capable of recording and reading Linear Stereo disappeared quickly after the introduction of HiFi Stereo, Chances of finding a VCR that is capable of Linear Stereo are slim and finding a pre recorded tape with such audio track is even slimmer. All VCR's are capable of reading and recording a mono linear audio track along the edge of the tape.
    Quote Quote  



Similar Threads