Panasonic VCR bad linear audio?

[pthebest19]

Hi. I'll try to quickly describe the situation.

I have a Panasonic combo NV VP23 and a NV VP 33. These have very good picture quality but bad linear audio (especially VP23). The NV VP 33 (which is the one with PAL60 support) malfunctions on me, after I foolishly put a dirty tape inside a long time ago. When I turned it on years after it had problems tracking the tape (cleaning it didn't help).

Then I also have a Panasonic NV HD647 I bought for SECAM tapes, but also plays NTSC in PAL60. This one has way better linear audio, but the video is clearly oversharpened. It looks some kind of filter to me.

I also found an NV HD675 on eBay which according to the manual has a native NTSC option and not NTSC 433 or PAL 60 which look worse. If it doesn't have the oversharpening problem I talked about I'd buy it immediately. Does anyone know? I have many NTSC tapes I want to digitize anyway.

I'm not looking for high end VCRs, as what I digitize is mostly TV recordings and I'm fine with an acceptable picture and audio. I just don't want loud audio hiss and white lines from oversharpening.

[hodgey]

The multi-system HD675 has mostly the same guts as the HD647 and is from the same generation, so the output is likely to look very similar. I have the HD630AM which is basically the same as the HD675 multi-system variant but without jog-wheel, don't remember it being overly sharp, granted I haven't used it much. These all have the CVC system that auto-adjusts sharpness and panasonic removed the ability to adjust or turn it off by the time these models were out annoyingly.

You may be better off with a different brand, or an older model.

[pthebest19]

As far as I know the NV HD line is from 1999, while the combo NV VP line is from 2004. The sharpening problem is in the earlier model in this case.

Do you know if the NV FJ series also have this issue?

[timtape]

Quote:

Originally Posted by pthebest19

...I'm not looking for high end VCRs, as what I digitize is mostly TV recordings and I'm fine with an acceptable picture and audio. I just don't want loud audio hiss and white lines from oversharpening.

I specialise in magnetic tape media and hardware. Apparent excessive audio hiss in linear audio playback is often due rather to a lack of audio clarity. The hiss hasnt got louder, the audio playback is more muffled and indistinct than it actually is on the tape. We turn up the volume but we just get louder hiss.

One obvious culprit is a dirty linear audio head. A cleaning tape can sometimes help.

Another is misalignment of that same head to the tape played. Swapping VCR's wont necessarily fix the problem as the recorded audio itself can be misaligned and for clearest audio capture the VCR's linear audio head needs to be well aligned to the tape played.

There is no easy VCR "front panel" user solution to this. AFAIK it was never provided although the manufacturers knew about the issue. Cost would have been a factor.

For audio cassettes, we could once buy various brand new Nakamichi decks which had front panel audio head adjustment. One or two models did it automatically or it was manually adjustable from the comfort of our listening position via wireless remote control! See attached image.

Not so VCR's unfortunately.

[pthebest19]

I manually cleaned this VCR less than a week ago, so that's not the issue. The same amount of hiss is heard in my 2012 captures using the same VCR, so it's not even that something got misaligned or broke.

You can hear the hiss in this capture I did (video was reuploaded by another user): https://www.youtube.com/watch?v=YeWVm2bJfso

As for the NV VP33 that doesn't work, it seems to me it was badly handled by someone else as I put it in the basement. If I hold the auto tracking button the picture doesn't roll, but the audio still won't play. I was told it can be repaired.

I also saw a NV HV60PX for sale which has true NTSC support. Does anyone know about that model? It should be from around the same time as the combo ones I have.

[hodgey]

Quote:

Originally Posted by pthebest19

As far as I know the NV HD line is from 1999, while the combo NV VP line is from 2004. The sharpening problem is in the earlier model in this case.

Do you know if the NV FJ series also have this issue?

From what I remember with my NV-FJ621, the output was very similar to the HD630AM, though it's been a long time since I've used it as it has some issues. The NV-HVxx/NV-MVxx came after, and have a different main video/audio IC to the older ones which may or may not be similar to the combo decks, I haven't used any of them so can't speak of how the playback is on those.


I agree with what timtape is talking about, though besides that there are a few of the later vcrs that seem to have crappy linear audio playback quality in general (e.g some of the very late model JVC decks have been discussed here before which seem to have some sort of distortion, 2 out of 3 LGs combos I have seem to have something causing high-pitched whine) which may or may not be design flaws. Whether this is something plaguing these panasonic combos I don't know, as I haven't used them, the youtube clip doesn't sound like it has excessive hiss or distorted audio at least.

[pthebest19]

I went for that NV HV60PX because it was convenient (as the seller offered bonus tapes, other than native NTSC), but anyway, do you think my issue with the VP 33 can be fixed?

The picture is stable only if I hold the auto tracking button, but no audio plays. I looked at it inside (and cleaned it too), and it looks fine to me. Last time I used it it was 2020 and it worked just fine. I noticed the audio hiss on my old captures was way louder than the HD647, but not as loud as the NV VP 23 which was used in that video I linked.

[hodgey]

Picture only being stable if the auto tracking button is held seems like a really strange problem. Maybe one of the keys that adjust tracking on the front are stuck or something?

Alternatively, if it's both completely failing to track and there is no audio either that sounds like the audio/control head could be dirty (which could be caused by a dodgy/dirty tape), damaged, or the cable to it is bust/loose.

[timtape]

Quote:

Originally Posted by hodgey

... the youtube clip doesn't sound like it has excessive hiss or distorted audio at least.

Yes I've heard a lot more hissy and distorted. Of course linear audio is a lot hissier than HiFi audio. A better comparison would be the OP playing a tape carrying both linear and HiFi audio, and switching between the two.

[pthebest19]

That was a tape I recorded when I was pretty young. Back then I had an Aiwa 2 head VCR which didn't record good sound, sometimes it would be very quiet (and in this case the hissing can be heard better).

I compared the same tape during the Italian dub credits (which are silent) on the NV HD647 and the hissing is a lot quieter. Does it have to do with the audio head?

[timtape]

Quote:

Originally Posted by pthebest19

That was a tape I recorded when I was pretty young. Back then I had an Aiwa 2 head VCR which didn't record good sound, sometimes it would be very quiet (and in this case the hissing can be heard better).

I compared the same tape during the Italian dub credits (which are silent) on the NV HD647 and the hissing is a lot quieter. Does it have to do with the audio head?

It's always easier hearing what you are hearing. Fortunately this forum accepts uploads of video and audio files. Any chance of a sound clip from your 647 for comparison?

[pthebest19]

I'll put a comparison here from a 1992 recording. It's a cartoon clip so you can see the sharpening issue a lot better.

[timtape]

For the audio I thought you were going to compare the two decks on the same Italian dub credits section for the background noise.

[pthebest19]

Right now I have to take my PC to the repair shop and I didn't have a clip ready for that. I'll post it at the end of the week.

You can hear the audio hiss is louder on the first VCR, right?

[timtape]

We always need a reference like using the same tape section played on different VCRs. Ideally we would get to play the exact same physical tape as you rather than have to put up with a digitised version which is a step removed, where we hear "the tape" but mediated through the VCR it was played on. There's a good reason service technicians used strictly calibrated test tapes for aligning VCR both picture and sound.

[dpalomaki]

FWIW, sometimes hiss can be "baked in" to the original recording. Often a result of AGC in the camcorder or VCR and/or use of poor mics or mic placement.

One way to check this may be to play a blank tape, or check playback of a tape just recorded on the same machine to verify it is not a head alignment issue. If the hiss is less it is an issue with the tape.

Perhaps a paradox but hiss may be more evident on a tape played in a system with wider linear track frequency response. Also presence or absence of Dolby coding/decoding could effect the perceived hiss. Use of headphones for monitoring audio will generally make any hiss present more apparent.

Audio editing tools like Audition can be used to filter hiss.

[pthebest19]

That NV HV60PX has eccellent NTSC playback and audio, but the PAL signals seem to have more visual noise, and I see dark smears on bright areas. I'll post here two comparison clips on a black screen with the TV logo.

[BartoloniDavy]

VCR_comparison.mpeg
the audio frequencies seems "cutted"

can be an issue caused by acquisition software?

[timtape]

Yes but the spectrogram can also mislead. Remember it's not the sound itself. Always good to supply the sound as a file as well.

[dpalomaki]

What is the screen shot?
Looks like three different short clips.
What was the source of the clips?
(The thread goes back 18 months.)