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-   -   JVC SR-V101US buzzing audio issues? (https://www.digitalfaq.com/forum/vcr-repair/7773-jvc-v101us-buzzing.html)

MrEightThreeOne 01-31-2017 06:17 PM

JVC SR-V101US buzzing audio issues?
 
Hello! I guess this is my first post to this forum! First, I want to say thanks to all who have contributed to this forum over the years -- I love VHS stuff and it was a tremendous help in picking out the right hardware to do captures.

Unfortunately, after finally investing in a high-end VCR after all these years, the one I ended up grabbing is...well, the audio isn't very good. Well, it is, except for one issue -- there's an obnoxiously high pitched buzz during playback, and ONLY during playback. An old Sony SLV-N71 VCR I've used doesn't have this issue on the same capture card, so I know it's a fault on the VCR's side (plus, it doesn't do it when the tape is stopped). Here is a little sample of the noise I'm dealing with:

http://www.mediafire.com/file/v40akmf1fds7xdj/Buzz.wav

This VCR seems to be operating perfectly fine otherwise, so I'm not sure why this is the case. I've thought maybe it's interference, but could it really be? Moving my cell phone around didn't seem to do a whole lot of good. Or maybe it's dirty heads? But I feel like if that were the case, I'd be getting popping and cracking instead. This occurs both on tapes with linear AND hi-fi audio, and on SP and EP tapes. I dunno, do any of you have an idea of what it could be? Thank you in advance.

lordsmurf 02-01-2017 12:45 AM

Welcome. :)

Hmmm... several possibilities here.

- full dynamics of audio not picked up by Sony consumer deck
- JVC bad caps (rare)
- JVC audio options wrong, set on mono; JVC mono known to be blah
- tape tracking better in Sony; tracking often causes audio issues
- source tape conflicting with JVC
- power interference, must put on UPS to filter (AVR)
- dirty heads possible, but very unlikely

Attach audio clip to forum, I cannot download from Mediafire.

MrEightThreeOne 02-01-2017 07:10 AM

1 Attachment(s)
Ah, my apologies. Here is the attached file.

I'll look closer into this when I have time later today, but thank you for the suggestions.

Something worth mentioning...This happens on all tapes I've tried on the JVC. I think all of them are linear audio though, that might have something to do with it. I'll probably look for a hi-fi tape today in any case and see if that makes a difference. Changing the audio options didn't really seem to do me any good, unfortunately.

I want to say it might be power interference, perhaps. Will give that a try if I can.

-- merged --

Okay, I just took a deeper look into this. It seems there's a problem on the hardware level with the audio. The VCR always says it's playing on the linear track on the OSD, even if the tape has hi-fi. What's more, though, changing the options on the audio monitor doesn't seem to do anything at all! It seems to be playing from the hi-fi track on tapes that have it, or at least attempting to (the audio on one hi-fi EP tape sounds way too good to be linear), but I don't seem to have any real control over it.

The seller I bought from has two other units in stock so I can at least swap those out for a try instead, but it's also going to be a bit of a pain because I already bought a remote and the cables and all. Still sitting on whether I really want to stick with a high-end VCR in any case (it was a bit of a hefty investment and the amount of payoff wasn't quite as big as I was hoping), but I guess I'll just wait and see. Thanks for the help in any case!

lordsmurf 02-01-2017 08:23 PM

That sounds like power interference. It could be external (your home/office) or internal (in the VCR).
Every product line has some duds.
The model line is fine. The SR-V10/101 is an amazing unit. I have several.

MrEightThreeOne 02-01-2017 09:01 PM

Alrighty. I'm pretty sure it's internal, but I will try it in another room, and if that fails, I'll try it in another building entirely. Thankfully I have a way of doing that. This is kind of an old building so I wouldn't be surprised if maybe that was an issue. Though the fact that I can't switch audio modes is still quite puzzling. In the end I'll likely swap it (or just send it back and not get another; that has more to do with me questioning the investment rather than the quality of the VCR, it's amazing otherwise and I have never seen better picture quality out of VHS), but again, thank you for your input! Really appreciate it!

deter 02-03-2017 02:25 PM

Wow, that is a new sound issue, I will tell you what, I have a better machine than the SV10, it blows it away. Not only will, The JVC 9900 and the JVC 9800,smoke this unit for quality and picture, will give you a good deal. Since you have the remote you don't need a remote.

My units work perfect.

I would like to get a hold of this unit SV1, just so I can look at it and repair it. This is a problem that I have not seen before.

Would be willing to do a swap and trade. If you can get a better working unit from the guy, go that route and maybe just keep the broken unit, cause it is worthless, it will cost at least $150 to fix, that is my guess. You need someone who can actually fix it, which is more rare.

Also have AG1980 units which smoke all of these JVC decks out of the water, it is the best VCR ever made, and they are fully restored. However they come with a nice price tag. Yes on some tapes the JVC 9000 series does a better job on the tapes. In my opinion you need both.

Yes I have owned SV10, SV100 and the JVC 7800 (which is the same), and the 9900 and 9800 are way better VCR's.

lordsmurf 02-03-2017 08:05 PM

Quote:

Originally Posted by deter (Post 47586)
I have a better machine than the SV10, it blows it away. Not only will, The JVC 9900 and the JVC 9800,smoke this unit for quality and picture
Also have AG1980 units which smoke all of these JVC decks out of the water,

Nah, not that big a difference. They all play different with different tapes. Each can have its moments of stellar performance, and irritating performance.

Comparing those VCRs is like comparing 3 fine wines. By this point, you're in "quality land". Now the decisions come down to when (ie, which tape needs it, which wine to have with this meal), and preference.

Usual scenario:
AG1980 is EP, sometimes SP
SR-V10 for many EP and LP
9600-9900 for SP, sometimes EP or LP

You have NR, audio, TBC and sharpness considerations, too. It's nuanced.

For linear/mono audio, the Panasonics work better. The JVC 9600-9900 can be better, too. I've not done a lot of SR-V10/101 mono audio. JVC doesn't always play nice with non-HiFi.

deter 02-05-2017 12:41 AM

Lord Smurf,

Yea the audio part can be an issue however you can record the audio from two different machines.

For example have a tape that crackles on the JVC deck but plays perfect on the AG 1980

However the tape has major ghosting issues. Have to use the JVC deck for video, it fixes the problem

Record the video on both units, pull the audio from the AG 1980 match the audio stream to the JVC video and we get the Best of Both Worlds.

The JVC 7800 or SV 1 is a lower quality picture than the 9000 series, but yea they are not bad VCR's...Have used them...

lordsmurf 02-05-2017 12:53 AM

Quote:

Originally Posted by deter (Post 47633)
you can record the audio from two different machines.

This is very true. I've done this many times over the years. Audio from one VCR, video from another. :congrats:

dpalomaki 02-08-2017 09:05 AM

2 Attachment(s)
An unusual noise waveform
Some 30 Hz and harmonics, plus an unusual few cycles of ~8 kHz ringing every ~1.4 msec
Waveform and spectrum .jpg attached, if that helps sort it out.

MrEightThreeOne 02-08-2017 01:58 PM

Status update on this!

So, the eBay seller gave me another SR-V101US, and...it looks like this is an issue on my end. However, there's something even more peculiar -- this only happens on linear audio. If I have the VCR set to hi-fi, it's fine! I think it's a power interference issue at my college apartment. Sooner or later I'll be able to take this VCR back home and see if it has the same issue.

The other VCR is still broken though; as it turns out, yeah, it only plays linear audio after all. It never goes to hi-fi, no matter what I try to do. The replacement VCR is properly able to change to hi-fi audio like it's supposed to, so there was a problem with it, I just wasn't able to pinpoint it. All my personal tapes are hi-fi (did I mention my dad originally spent $600 on a VCR that could do 4-head and hi-fi back in the mid 80s? He kicks himself for making that purchase to this day, haha), so for the most part this won't be an issue for me, but it's still odd.

Then again, my apartment is a bit old, so it isn't hard to imagine there could be some sort of power interference issue.

On the topic of this, I should mention I went back and forth on buying a high-end VCR for almost four years before finally settling on this. This is going to be my only high-end VCR for a good amount of time and probably ever, since I won't be running a business for this sort of thing or anything. I know the common ideology is that you need more than one VCR to do the job correctly, but I just don't have that kind of money or room.

Although then again, y'all would absolutely hate my setup anyway and probably die five times over for the amount of amatuer-ish things I do, heh. Just for starters...I use a Dazzle as my capture card. Please don't kill me.

In case I haven't already been pelted with tomatoes for saying that, I'll also say yeah, I'll probably do the two-VCR route for linear audio. The video quality on this VCR is outstanding, it's really blown me away, and since only a few tapes of mine have linear audio (mostly ones I bought from the thrift store that have abysmal audio quality, probably because whoever originally recorded them cheaped out on whatever VCR they used), I will go that route. My other two standard VCRs are able to do it just fine as far as I know.

Once again, thank you all!

lordsmurf 02-08-2017 08:55 PM

The Dazzle is a potential weak link. That could be your problem, too. It's known-problem brand, with very few specific cards having passably acceptable results.

As a test, try to bypass all video, and just record sound from your audio card with a program like Sound Forge. What are the results?

MrEightThreeOne 02-08-2017 09:45 PM

Oh, it's definitely not the Dazzle. As I said, this only happens on linear audio, and only while a tape is playing. When I switch the VCR to hi-fi, it's fine. Plus in the past, I've been able to record from my Dazzle audio with little trouble (such as capturing video game console, which actually was what I initially bought it for). I think it might just be linear VCR audio being bad.

I think I'll quit messing with it for now, to be honest. Right now I think the more important issue is that the defective unit (I have two units now, the broken one and the working one) simply won't switch to hi-fi at all, where the working unit does. I think I've gotten my setup working to my satisfaction and next time I go home over a break (which sadly isn't until March), I'll be able to do some more diagnostics. I'm stuck with only a fairly weak laptop down at college, where back home I have a nicer desktop computer to toy around with plus the other two regular VCRs to play with too (A Sony SLV-N71 and a Hitachi FX623).

To get everyone up to speed on this, I don't think I've been that clear, so let me explain what happened...
* I bought one SR-V101US, but it had the bad audio issue so I posted about it
* After posting, I figured out it was more than just that -- the VCR wasn't switching between linear and hi-fi audio as it was supposed to, and my lack of familiarity with how it worked led to confusion on my end
* I contacted the seller I bought it from, he apologized and offered to send another unit in exchange for returning the defective one, so I said yes
* He decided to not require me to send the old one back after all, and gave me a whole 'nother unit. This one didn't have the linear/hi-fi switch problem, but still had the hum on the linear track, but hi-fi was fine, leading me to believe it's an issue on my end or just linear audio being bad by nature

Although I'd like to just send the defective unit back, but I'm still trying to get that all worked out as well.

dpalomaki 02-10-2017 08:29 AM

Quote:

but still had the hum on the linear track,

Read more: http://www.digitalfaq.com/forum/vcr-...#ixzz4YI5jTITA
It more than just hum, a lot more. (See the wave forms in an earlier post.)

The ~8 KHz frequency is about half of the horizontal frequency
the 30 Hz is the NTSC frame rate.
That could be the result of sync bleed into the audio.
Trying another audio recorder can confirm it is in the VCR, as can playing a tape with the audio only connected directly to a stereo system's AUX input. If the fault is with the VCR you should hear both the hum and some spatter and hiss. Minimize the bass setting to better hear the spatter and hiss.

However, the waveform frequency analysis shows a peak every ~700 Hz (the ringing every 1.4 mSec).
The ringing is almost as if the unit was getting hit by a periodic radar pulse (is the unit under an airport approach by any chance?) or similar EMI source. The linear heads may be picking this up, but the Hi-Fi heads should be more or less immune to it. In that case changing the orientation of the VCR may effect the level of the noise.

Among serious users Dazzle is not a well regarded capture device. It boils down to whether or not you are satisfied with the results you get with it.

Your "bad" VCR could serve as a source for parts in the future

MrEightThreeOne 02-11-2017 09:15 PM

I'm not near an airport, but I'm in an apartment, so really it could be any number of things (the guy above me might have a radar for some reason, but meh). Either way, it's a fault on my end, I'm pretty sure of it. Maybe the person living above or below me (I'm on the second of three floors) has something, or maybe it's a thing going on next door, who knows. Either way, when I go back home, I'll be able to see if I have the same issue, so we'll see.

And yeah, I'm well aware the Dazzle isn't highly regarded, and heck I'm not even sure I totally think it's that good (the worst aspect of it is an annoying checkerboard dithering pattern on s-video), but for me I think it gets the job done. I may invest in a better one down the road, but for now the Dazzle mostly does what I need it to.


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