rls@ihu1g.UUCP (r.l. schieve) (08/05/85)
My VCR (JVC HRD225) is several years old and from the time when Dolby Stereo was the latest push. At the time I bought it the better tapes I rented were recorded in Dolby Stereo. Now the lastest is Hi-Fi. Rented tapes marked Hi-Fi seem to be still stereo and I assume I should play them with the Dolby noise reduction turned off. Are there any compatibility problems I should know about or any way to get more out of my present set up? I have the option of palying the audio through my stereo receiver or through my stereo TV. Rick Schieve ...ihnp4!ihu1g!rls
jerry@psivax.UUCP (Jerry Askew) (08/08/85)
First off, forgive me if the format is kind of dull because this is my
first article.
In the beginning...(of VHS tape,) the format was quite simple. The tape
was divided into 3 sections. Starting from the top, the first section was
allocated for audio. The audio track is about 1mm in thickness and
contains audio information recorded in the usual format that we are all
used to (linear recording, just like cassette tape.) The second section is
dedicated to the video information (More on that later.) The third section
is given to the control track. This track, also 1mm wide, contains a 30hz
pulse that helps the recorder to synchronize its video heads with the video
information that is on the tape.
Video information is laid down in the video area using a recording
technique known as helical scanning. The video information is put on the
tape in diagonal 'tracks'. The reason for this is that the spinning action
of the heads makes the relative head to tape speed approx 3 metres per
sec!!! this gives the necessary fidelity to reproduce a video signal whose
upper freq limiit approaches 4mhz!
Somewhere along the line, some brilliant engineer figured that if
video could benifit from the extrordinary bandwidth & flattness of helical
recording, why couldn't audio?? Hi Fi was created. The only problem now
is where to put the helical audio tracks. A new recording technique was
developed...called deep layer recording. Hi Fi audio information is
recorded UNDERNEATH the video information, therefore you have 2 independant
stereo audio 'channels' on a hifi recorder.
The summary of the above is that hifi audio is COMPLETLY seperate from
standard 'linear' stereo audio & should have no effect on the operation
of a 'linear' recorder. Most tapes that have hifi tracks on them are
recorded in dolby stereo but this is not required.
Hope that my fist try helped somebody!
Jerry Askew
psivax!jerrybrown@nicmad.UUCP (08/08/85)
In article <668@ihu1g.UUCP> rls@ihu1g.UUCP (r.l. schieve) writes: >My VCR (JVC HRD225) is several years old and from the time >when Dolby Stereo was the latest push. At the time I bought >it the better tapes I rented were recorded in Dolby Stereo. >Now the lastest is Hi-Fi. Rented tapes marked Hi-Fi seem to >be still stereo and I assume I should play them with the >Dolby noise reduction turned off. Nope, play them with the Dolby switch ON. If you were to look at the original boxes, most are marked Hi-Fi stereo, Dolby stereo linear track. >Are there any compatibility problems I should know about or >any way to get more out of my present set up? I have the >option of palying the audio through my stereo receiver or >through my stereo TV. I am assuming that you mean you are using the line out jacks of the VCR to the line in jacks on the TV. If you mean MTS TV receiver, nope, no stereo. Personally, I would use the stereo receiver (which I do) and not the TV speakers. Too close together. Can't tell the stereo when they are only 36" apart. -- |------------| | |-------| o| HRD725U & PV9600 Mr. Video | |AV-2010| o| |--------------| | | | | | |----| o o o | | |-------| O| |--------------| |------------| VHS Hi-Fi (the only way to go) {seismo!uwvax!|!decvax|!ihnp4}!nicmad!brown
seifert@hammer.UUCP (Snoopy) (08/15/85)
In article <632@psivax.UUCP> jerry@psivax.UUCP (Jerry Askew) writes: >In the beginning...(of VHS tape,) the format was quite simple. > [...] > Somewhere along the line, some brilliant engineer figured that if >video could benifit from the extrordinary bandwidth & flattness of helical >recording, why couldn't audio?? Hi Fi was created. The only problem now >is where to put the helical audio tracks. A new recording technique was >developed...called deep layer recording. Hi Fi audio information is >recorded UNDERNEATH the video information, therefore you have 2 independant >stereo audio 'channels' on a hifi recorder. Ah, *VHS* invented HiFi! Gee, I didn't know that! Has anyone told Sony about this? Well, you'll have to excuse me, I'm late for my NEWSPEAK class, and Professor Orwell doesn't like tardiness. Snoopy tektronix!hammer!seifert Why do you think I believe what you've said? Few of your words ever enter my head. -Emerson, Lake
jerry@psivax.UUCP (Jerry Askew) (08/20/85)
Flame Flame Flame.... I do not claim that my articles are absolutly accurate in every respect. My Hi-Fi article was intended to enlighten people in the technical aspects of VHS HI-FI recording... the other B.S. was in there to lighten the subject and provide easier reading. The article was not intended to imply that the VHS people invented Hi-Fi or even deep layer recording. Jerry Askew [stupid disclaimer here]