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  1. Hello everyone!

    Up until now I capture only videos from the same source (My father's old Video Camera). But today I moved into some tapes I want to archive which were taken not by my father, but external Camera man (for an event).

    I notice (on 2 different tapes) - that some section has no audio at all - and a single section has only some of the audio (you can hear background music, but not the person talking). Playing around with the VCR settings, I was able to change the Audio settings from HiFi to Normal (Left and Right were also options). On "Normal", I was able to hear the missing audio sections, and I wonder what exactly happening?

    Also, playing around with section with no Audio with them - I noted I can still hear "Hissing" sound. I was sure the hissing sound was a byproduct of the old Video Camera and the fact it had build-in mic. I'm attaching a video with background sounds so you can hear the hissing. I think it's normal to all Analog, but just making sure

    Thanks!
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  2. Originally Posted by Okiba View Post
    Playing around with the VCR settings, I was able to change the Audio settings from HiFi to Normal (Left and Right were also options). On "Normal", I was able to hear the missing audio sections, and I wonder what exactly happening?
    VCR and camcorder audio features evolved over time. Originally there was only linear (later renamed "normal") audio, which is recorded on the edge of the tape much like an audio cassette. But because videotape moves comparatively slowly vs good audio-only recorders (esp in 6-hr SLP/EP mode), the overall quality of the original linear/normal track can sound muffled and hissy. The HiFi audio feature was invented to work around this issue: instead of the slow moving linear tape edge, audio is recorded by additional spinning heads attached to the video drum, which lay down audio in the same high speed diagonal stripe pattern as the video. Theres a bit more to it involving FM multiplexing etc, but the takeaway is HiFi is significantly better sounding than Normal/Linear (aside from the annoying buzz you pick up when tracking isn't quite perfect).

    This dual audio system can be confusing if you didn't come of age in the VCR era. As with any new feature, HiFi was an expensive option at first that slowly became mainstream. There was a transitional period where some VCRs and camcorders included the HiFi feature, and some didn't, depending on price tier. Most of the full-sized and VHS-C camcorders sold were budget Panasonic models without the HiFi audio feature, so most "family event" tapes only have normal linear audio.

    If such tapes are played on a more common modern HiFi VCR you won't hear any sound if the VCR happens to be switched to play HiFi only, or L or R channel only. Most VCRs have an automatic override that will default to the linear normal track if the VCR fails to detect a HiFi track on the tape, but a few VCRs can be locked manually into a HiFi-only setting: if your VCR is one of those, you'll need to manually choose Normal to hear any audio if the tape lacks a HiFi track, and that audio will indeed be hissy, esp in quieter passages.

    Note also, VHS and VHS-C camcorders tended to use a slightly weird compact mechanism compared to standard VCRs. This can lead to finicky setting of the tracking control when playing the old camera tapes on a VCR today: it can be hard to find a tracking setting that is equally good for both the video and the HiFi audio. If you discover the HiFi audio keeps cutting in and out abruptly at the best tracking setting for the video, or it buzzes a lot, you may need to give up on the HiFi track and manually select Normal/Linear. It won't sound as good, but it will be consistent and reliable.

    The tapes that seem to have sections with no audio at all on either HiFi or Normal settings were probably the result of mistakes in camcorder operation. If someone accidentally plugged their headphones into the camera MIC jack instead of the headphone jack, then just left the headphones hanging around their neck, they might not notice they had cut off the camera internal microphone and weren't picking up any sound. A lot of consumer mics in those days had a sliding on/off switch that was easy to knock out of position: if it got set to OFF and and you didn't notice, no sound was recorded. Etc. Because the hissing noise is inherent background in the Normal Linear audio system, you will still hear hissing (and maybe a humming) when there is no other real sound recorded on the tape.

    .
    Last edited by orsetto; 21st Sep 2020 at 20:52.
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  3. Member dellsam34's Avatar
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    Some VCR's did have Dolby noise reduction on the linear track but that won't help you if the audio track was not recorded the same way, I'm not sure if any consumer camcorders did have Dolby on the linear audio track because it defeats the purpose of making a cheap camcorder by skipping the HiFi feature and paying the expensive Dolby licensing fees.
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  4. Member dellsam34's Avatar
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    Looking at that sample you posted it looks like a DV footage unless you took the VHS frame and cropped all around.
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  5. Member Cornucopia's Avatar
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    There are 3 other possible scenarios, but are rarer and I don't think they apply here.
    1. Hifi heads record deeply while video heads record more shallowly on the tape. If the tape was originally recorded (with e.g. music on the hifi audio), but then was later re-recorded by a cam/recorder that had no hifi heads, and the erase head wasn't strong, the original hifi wouldn't get completely erased, even though the orig video would. And then the new video would be put down on top of the existing hifi audio, with the new normal tracks (vox) on the edge. I have experienced this.
    2. Next, IIRC, some decks & camcorders (more pro/semi) might have been able to send independently-sourced tracks simultaneously to each of the hifi stereo pair channels as well as the normal track(s), in essence acting as a 3 (or 4) track recorder. Of different quality capabilities, but still possible. That's the least common scenario.
    3. A little more common is the post-recording sound-on-sound re-recording capability of the linear tracks (not avaiable to the hifi tracks for reason of the previously mentioned deep/shallow erasure operation with the co-located hifi & video tracks).
      This is unlikely though if the new linear sound is supposed to be live, yet synchronous with the existing video.

    Scott
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  6. Thank you orsetto, dellsam34 and Cornucuopia!

    First of all, good to know all that. I did some research based on your comments. It seems my VHS is smart enough to handle that automatically. On the Camcorder footage it only had Normal as option. And if the hissing in the video I shared is acceptable and indeed a problem of Linear audio. That's good news!

    The other tape that was taken with a different Camcorder, had HiFi support in it. So the VHS selected HiFi - however, sound was missing. Switching to normal seems to be fixing it. So it's either a fault of the Camera man, or any of the technical error you guys mentioned. I will keep it on Normal - and will check future captures. If they have HiFi - I'll make sure all sound is there.

    Thanks!
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