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  1. Hello

    I hope to find someone that could help me to find a solution to this annoying problem, or at least get a better understanding of it.

    Lately I have captured audio from some of my HI-FI vhs. I often run into this problem where I get some kind of buzz that seems to be located in the bass range frequency. The buzz doesn't occur on all parts of the audio, and seems to be more present when it involve a female voice. It pisses me off because most parts of the audio are awesome. But these random buzz just ruins the whole thing.

    Most of the time cutting around 50-150 HZ ( depends of the part of the audio) helps. But I'd rather avoid to cut those frequency if possible.

    The problem is no present on mono track. I have many vcr, and the problem happens with all of them (with many different tapes). I've try to move the vcr, change rooms, to plug it into my Tv intead of my computer, doesn't change a dam thing...

    At first I thought the problem was with my tape which was damaged. But with the issue showing up with 4 consecutive tapes I'm starting to think the problem is elsewhere.

    Does anyone knows the cause of this, any solutions ?

    See an exemple in attachment (sorry it is in french). You might have to raise the volume to hear clearly the problem.
    Image Attached Files
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  2. That is (unfortunately) a very common symptom with HiFi tapes: aside from creative post-capture filtering there isn't much we can do about it. The intermittent buzzing is inherent in the HiFi audio technology, due to a combination of issues (inconsistent sensitivity to input level overload at certain frequencies like female voices, tracking deviation due to the spinning heads laying down the audio tracks in slightly different position from the video, etc).

    Some brands and models of HiFi VCR handle this a little better than others, but it can be difficult/impossible to eliminate completely. Ability to play HiFi with less buzz varies with brand name, and further between models within the same brand (i.e., some inexpensive Mitsubishis are great at this while very expensive premium Mitsubhis are about as bad as JVC or Hitachi, most Panasonics are better at HiFi than average but don't handle HiFi on commercial movie tapes or JVC recorded tapes too well). Of the hundreds of HiFi VCR models offered over 30 years, there were perhaps just a dozen rare decks specially designed to minimize this buzzing artifact (and even they can fail if the tape has a seriously misaligned HiFi recording on it).

    The biggest factor is the VCR that originally recorded the tapes. Many, many VCRs deviated significantly off spec in recording their HiFi tracks: we didn't notice at the time because the VCR will usually play its own HiFi reasonably well. Years later as tapes age, VCRs age, and we try to play the tapes on other models the buzz becomes more annoying. The automatic tracking feature often makes it worse: the system constantly adjusts tracking for the best video which can throw off the HiFi tracking. If you haven't done so already, try switching your VCR to manual tracking (most do this if you press the channel up or down button during tape playback). Tap the channel buttons briefly in each direction over and over until you hit the best compromise of minimal HiFi buzz and a decent video picture. Some tapes have such difficult HiFi that you can't lock onto it reliably in manual mode, or reducing the buzz makes the video look worse: if that happens, reset the VCR to automatic tracking by ejecting the tape and reloading it.
    Last edited by orsetto; 23rd Apr 2021 at 02:23.
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  3. Member
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    Great response orsetto. As a kid I used to record CDs from the local library (cough) in an "audio only" mode on my VHS many moons ago ( I think it was a Grundig VCR ) . I did notice a low frequency audio buzz, mainly on headphones, and if my memory is accurate it was always worse on one channel more than the other , I always thought it was a fault of the VCR. I still have the tapes.
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  4. Thank you for your answer Orsetto. That's what I was affraid of... Was just hoping that somebody found a way to deal with it with some kind of filter/mixer on pre-record.

    Do you have any name for those rare decks specially designed to minimize this buzzing artifact ?

    Thanks again for your information. It is very appreciated !
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  5. The exclusively-JVC-brand "WVHS" analog HDTV decks include circuitry specifically designed to address this issue, but I believe they were NTSC-format only. Originally intended just for the domestic Japanese luxury market, they failed due to very high retail price. Surplus stock was liquidated thru an American satellite TV service, so some made their way over to USA. These WVHS decks are notoriously fragile and just about impossible to get repaired, so very very few survive 100% intact today.

    A couple of inexpensive midrange late-model Mitsubishi VCRs are known for exceptionally good HiFi tracking: they don't have dedicated circuitry to clean up the buzz but their basic tracking is so precise it helps reduce it noticeably on many tapes. The USA/Canada models were HS-U448 or 449 (VHS) and HS-U748 or 749 (SVHS), I don't know if there were direct PAL equivalents.

    A handful of large professional TV-studio-grade SVHS models approach the HiFi performance of the JVC WVHS, but here again supplies are scarce and repairs difficult to impossible. Panasonic and JVC offered a couple of these in both PAL and NTSC countries: the electronics are not durable and many have now irreparably failed. Sony had the SVP-5600 and SVO-5800: these are tougher and more durable with reliable electronics but are relatively uncommon. Sony apparently sold more in PAL format than NTSC: seldom seen in USA/Canada but they pop up often in Germany and Israel. Drawbacks with any of the large pro decks: SP speed only (no LP or SLP/EP playback), size and weight makes them prone to catastrophic shipping damage, most have not survived in good condition, and nobody will service them anymore (no spare parts).

    Probably the most realistic option is to use a more commonly available VCR, adjust the tracking for minimum HiFi buzz, and try to filter the buzz post-capture as best you can. If the tape has extremely difficult HiFi, sometimes the only solution is to switch the VCR to backup monophonic linear audio track: this usually eliminates all traces of the HiFi buzz, but you lose stereo and may need to filter some hiss or steady hum. This method isn't recommended with modern JVC brand SVHS VCRs, which have very poor linear audio performance.
    Last edited by orsetto; 23rd Apr 2021 at 21:48.
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  6. Very nice and explicit answer Orsetto. Thanks for sharing your knowledge and your time. It is very generous of you!
    Since I live n Canada, I will see what I can find around here.

    Thank you again!
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