Audio buzz during recorded VHS playback and capture?

[monks19]

Hi. I'm having some audio problems with some of my recorded vhs and they have a terrible buzzing noise during playback/capture (at only "Normal" mode. See video sample attached below).

Any way to improve this without destroying the integrity of the audio too much ? I would use the "noise reduction" filter normally (Adobe Audition), but the results were not good at all. Then again, I may be missing steps in order to achieve this.

Can anyone please help me out ? That'll be greatly appreciated.

Thanks to answer.

[lordsmurf]

What VCR, what capture card?

Most often, buzz is not content-based, but playback issues with the VCR (either unit or model), due to the tape properties, sort of a shared-fault problem.

But sometimes it can also be the capture card.

Is your gear on UPS? Bad power can be to blame as well.

Just downloads the clip ... yuck.

Timing errors all over. That should never look so bad. Again, what VCR?

I don't hear any buzz. Buzz is low. What I hear is high-pitched whine. While that can be caused by the VCR, most often it's a record-time issue, baked into the tape. And those must be removed. It's a SNR issue, too much noise, gain isn't loud enough on the content. For me, this is somewhat simple to filter out in SoundForge, without any (or too much) harm to the audio quality.

[monks19]

Hi. The VCR is a JVC SR-V101US (S-VHS). I just did another capture with another deck (JVC D-VHS HM-DH40000U, I don't know if this one is in your recommanded list) and the results seems to be a bit better (see attached sample) with the hiss reduction process (Adobe audition).

The capture card is a mini dv camera (Sony DSR PD170) that I use for the firewire port so the capture can go straight to the PC. I had too many issues with capture cards before (including ATI ones). I have a TBC wired between the VCR and the cam and everything is all plugged into a APS power bar.

NB: That noise isn't happening on any HIFI purchased vhs (althought the audio does rattle a bit sometimes and I have to play with the connectors at the back (S-VHS deck only).

Let me know what you think

Thanks

[latreche34]

The second sample still has a lot of vertical wiggle due to line time base errors, It's either the HM-DH40000U is not configured right, or it lacks the line TBC. If so then it should not be in the recommended list, though all D-VHS decks should produce rock steady analog video out of the S-Video out unless they are defective (at least the US and Japanese models).

According the the home page it does have a TBC:
https://www.us.jvc.com/archive/video...s/hm_dh40000u/

[timtape]

If the problem is on the tape itself and is more a high pitched whistle or whine it needs to be targetted, I mean really targetted, with very narrow band EQ. Contrary to many people's expectations (or hopes) standard Denoise or Dehiss tools are not very selective and tend to wipe out too much of the wanted audio. A Dehum tool may be useful here but it needs to be manually and accurately adjusted to the whine or whistle so that as little as possible of the wanted audio is reduced.

I'm unable to audition your audio at present. If you care to upload just a wave file of the problem audio I'd be happy to check it out.

Tim

[monks19]

Quote:

Originally Posted by timtape

If the problem is on the tape itself and is more a high pitched whistle or whine it needs to be targetted, I mean really targetted, with very narrow band EQ. Contrary to many people's expectations (or hopes) standard Denoise or Dehiss tools are not very selective and tend to wipe out too much of the wanted audio. A Dehum tool may be useful here but it needs to be manually and accurately adjusted to the whine or whistle so that as little as possible of the wanted audio is reduced.

I'm unable to audition your audio at present. If you care to upload just a wave file of the problem audio I'd be happy to check it out.

Tim

There you go, Tim. Let me know if you need a better audio sample.

[timtape]

Thanks but I'm unable to open the file. Is it Win Zipped? Could you just upload a plain . wav file instead?

Tim.

[lordsmurf]

7zip is way better than Winzip, and even often better than RAR (which I'm using less and less these days). If you don't already have 8zip, get it. It should be an essential tool.

[monks19]

@Lordsmurf. Your expertise on the matter (post #3) is welcome too ;-)

[monks19]

Quote:

Originally Posted by timtape

Thanks but I'm unable to open the file. Is it Win Zipped? Could you just upload a plain . wav file instead?

Tim.

Alright. Take 2 with winzip

[timtape]

Quote:

Originally Posted by monks19

Alright. Take 2 with winzip

Thanks but again, could you just upload a plain .wav file instead please?

Tim.

[monks19]

Quote:

Originally Posted by timtape

Thanks but again, could you just upload a plain .wav file instead please?

Tim.

Here it is.

[timtape]

Thanks.

If by "normal mode" you mean the linear track (not HiFi) those high frequency tones/harmonics are not on the tape because the linear track is not capable of recording that high, so it must be caused by something else in the chain and will be there in the background no matter what tape you play. Is the noise still there in HiFi? When testing this, I would listen to a quiet passage on a HiFi tape.

In a good playback system the main background noise you hear on the "normal" track should be a low level hissing. That buzzing/whining/ whistling sound shouldnt be there.

But the music we hear in your file has very little highs above about 5 or 6 kHz anyway. In my upload I just filtered out everything above about 5 or 6 kHz with a Low Pass Filter set at a Q of 3. Most of the wanted music is untouched but much of the nasty interference higher up is removed.

There will always be background noise especially in the "normal" or linear track. What makes it worse is poor playback which muffles the soundtrack and so the background noise seems louder. When the track is played back at its best the sharper clarity of the track tends to overpower the background noise.

That's always my approach. Play the audio back at its best and a lot of noise problems arent so bad, and we dont have to resort so often to complicated processing. In other words we try to fix the problem at its source.

Hope this helps,

Tim

[monks19]

Quote:

Originally Posted by timtape

Thanks.

If by "normal mode" you mean the linear track (not HiFi) those high frequency tones/harmonics are not on the tape because the linear track is not capable of recording that high, so it must be caused by something else in the chain and will be there in the background no matter what tape you play. Is the noise still there in HiFi? When testing this, I would listen to a quiet passage on a HiFi tape.

In a good playback system the main background noise you hear on the "normal" track should be a low level hissing. That buzzing/whining/ whistling sound shouldnt be there.

But the music we hear in your file has very little highs above about 5 or 6 kHz anyway. In my upload I just filtered out everything above about 5 or 6 kHz with a Low Pass Filter set at a Q of 3. Most of the wanted music is untouched but much of the nasty interference higher up is removed.

There will always be background noise especially in the "normal" or linear track. What makes it worse is poor playback which muffles the soundtrack and so the background noise seems louder. When the track is played back at its best the sharper clarity of the track tends to overpower the background noise.

That's always my approach. Play the audio back at its best and a lot of noise problems arent so bad, and we dont have to resort so often to complicated processing. In other words we try to fix the problem at its source.

Hope this helps,

Tim

Thanks for your input. It does really help. Sadly, there's no HI-FI on that tape (which is a copy. The original is long gone. I'm tracking it down as I write this). As for what may be causing this, I have no idea. I thought that it might be a hardware trouble, but I don't know what exactly. Having this deck examined and fixed is nearly impossible where I live (as there are no longer that kind of repair shops anywhere). My only resort would be trying buying a new one from lordsmurf in the future.

Thanks for your help and sample

[timtape]

Quote:

Originally Posted by monks19

Thanks for your input. It does really help. Sadly, there's no HI-FI on that tape (which is a copy. The original is long gone. I'm tracking it down as I write this). As for what may be causing this, I have no idea. I thought that it might be a hardware trouble, but I don't know what exactly. Having this deck examined and fixed is nearly impossible where I live (as there are no longer that kind of repair shops anywhere). My only resort would be trying buying a new one from lordsmurf in the future.

Thanks for your help and sample

Very hard to diagnose from afar. It being a VHS copy of a VHS wont help. For best picture and sound, yes finding an earlier generation tape should help, all things equal.

A most basic thing is to ensure a fully clean tape path. In a way the normal linear audio track is a great leveller. Being a SVHS deck with a TBC wont fix a dirty, worn or misaligned audio head. The bells and whistles in many a fancy VCR dont help.
If you cant do it yourself is it possible to find someone local competent to thoroughly clean the deck's tape path - manually, not just with a cleaning tape - and cast an eye over the deck to see if anything else obvious is in need of attention?

It may be the buzz/whistle is caused by incorrect/faulty cabling from the VCR or perhaps from radiation from a PC monitor or PC too close to the VCR. A good test is to disconnect the VCR from your setup and only connect the audio output leads to the inputs of a stereo amplifier, play the same tape and see if the buzz/whistle diminishes or disappears.