Crackly audio on tapes: JVC SVHS, ATI TV Wonder 600?
 

Hey everyone, thanks for looking.

Occasionally when doing lossless capture from JVC HR-S7900U SVHS > ATI TV Wonder 600 USB > HuffYUV AVI, I get crackly audio throughout. This seems to be related to the tape itself, as most tapes have zero issues, but some tapes have the same reproducible issue over the same timestamps in the capture.

I've swapped out cables, cleaned the audio head a few times since i've had the VCR, done some basic troubleshooting. Next step is to grab another VCR and see if I can replicate the issue.

Just wondering if anyone's ever experienced this on certain tapes.

Here's a sample (144 mb):

https://s3.amazonaws.com/public-nich...ckle-audio.avi

Thanks!

Have you added the Windows audio registry hack for the ATI 600 USB?

ATI made custom drivers for the eMPIA bridge, but forgot(?) to add audio controls. So the audio is maxed at 100%, and capture should not be 100% levels. It should be 50%. You add the value, make it 128 (half of 255 max), and that's all. If you've not done it, and need help, I can document the simple procedure here.

Wow, nope, never heard of it until now. I'm on windows 7 if that matters.

I'm familiar with editing the registry, so probably don't need to know into crazy detail, but yes i'd appreciate your input on what key to be setting for this to work. How will I be able to verify it worked correctly?

And is it odd that only some tapes are doing this? Guessing maybe only tapes that were recorded overdriven or something. I don't think virtualdub has an audio level monitor when capturing, maybe i'm wrong?

I was also going to experiment with the VCR audio options. There's several modes, for example HIFI, Normal, Mix.

So I found the key, it already existed. It was set to 128. Changing it all the way from 1 to 255 doesnt seem to have any effect. I was changing it, unplugging and plugging back in the adapter, and restarting virtual dub. Do I need to do a full system reboot?

sounds like clipping, distortion, because the input level is too high for the A/D converter hardware specs.
with me i had to switch off "HiFi audio level" and had to lower the volume slider bar also, for my capture system driver, none of my VHS tapes reach that clipping level anymore, so i guess there's still some sort of automatic gain controll.

Yup, turning off HIFI audio brought the levels down, but the sound wasn't as good.

I ended up completely uninstalling the ATI drivers and reinstalling a couple of times and then adding registry keys in a couple places and finally the levels dropped on the capture card.

Strange all line in and output's should be at "line level" not microphone level i guess, looks like completely wrong drivers, it's risky to change reg keys, and sometimes you have to these settings also a second time in another "key branch"

That's precisely the issue. It was oversight by ATI to not include the proper keys in their custom eMPIA bridge drivers. Unlike internal cards, with USB, you access the bridge, and the bridge controls the actual internal chipsets. Just bad software design, but the hardware is excellent, and sorting this isn't too difficult.

Capture cards have always been squirrelly, ATI especially, and sometimes complete uninstall and reinstall is the only solution. Remember, even ATI released an uninstall tool for this exact reason.

Glad to see that you've gotten it sorted, and hopefully you're capturing away now. :)

No. :disagree:

You know not what you're saying.

The ATI 600 USB, and many other cards out there, are completely known entities. No random "other branch" is required, and it's not wrong drivers. Part of the reason I founded this site 15+ years ago was to share specifics on how to use ATI cards (AIW at the time, expanded to the ATI 600 USB and clones in later years).