Audio capture problem

[Scuda]

I have an ATI AIW 9700 Video capture card. My son recently installed a new sound card (SoundBlaster?). I'm trying to capture VHS to my hard drive. I have sound when I'm playing the video from the camcorder to the computer. When I capture it, I still hear the audio but when I play back the captured video, there's no sound. I have tried capturing it using DVDWS and the ATI capture software. Please keep in mind that I'm planning on finishing the DVD using DVDWS. I have XP on the computer. Any suggestions on where I'm going wrong. Thanks.

[theDruid]

Did you have this working before the new soundcard was installed?

Where is the audio cable from the capture source plugged in to? (sorry if this is a stupid question - I'm not at all familiar with AIW's)

Have you checked the 'recording source' in the windows mixer?

(if you're not sure how to do this, click Start->Run then type in sndvol32.exe /r and you should see your mixer controls for recording.)

cheers,
mcdruid.

[joecav]

While capturing, make sure you have your antivirus (especially Norton) turned off. I had severe audio problems until I discovered the conflict. Try that and shutting down your firewall too...just for good measure. This is, of course, if the previous post didn't solve your problem.

[Scuda]

Have you checked the 'recording source' in the windows mixer?

(if you're not sure how to do this, click Start->Run then type in sndvol32.exe /r and you should see your mixer controls for recording.)

I ran that last night and wasn't sure what to look for. The mixer control panel popped up and everything looked fine. Should any of those be checked?

Joecav, I always forget about the antivirus software. I'll check that out tonight. Thanks for the suggestion.

[theDruid]

Scuda, what you're looking for in the mixer properties depends on how you have the the cables etc.. plugged in for capture.

As I said, I'm not familiar with the AIW, but I'd guess that the normal way of setting up to capture would be to have an s-video or composite cable plugged into the capture card to get the video stream, and then another cable (like a headphone jack) plugged into your soundcard - to get the audio stream. This cable is most likely plugged into the Line in on the soundcard.

If that's how you've got it all plugged in, then it's possible that you can hear the sound when you playback the VHS, but that the PC is not set up to record that sound.

This happens if you've got the level turned up for Line in in the Playback mixer (and Line in is not muted), but you have not got the level turned up, and the source selected in the Recording mixer.

You saw the Recording mixer by typing in sndvol32.exe /r, and you can see the Playback mixer if you go to Options->Properties on the mixer, and change the setting:



Like I say - this might not be quite how it works with your set-up, but it's a fairly standard way of connecting up for capture.

So, if your audio cable is plugged into Line in, then you need to have Line in checked in the Recording mixer, and the level turned up to 90% or so.

cheers,
mcdruid.

P.S. If you disable your firewall & antivirus, make sure you disconnect from the web too!

[Scuda]

Druid,
YOU ARE A GOD! It worked. Thank you very much for all of your help. Joecav, thank you also. I believe it was a combination of the two ideas that put me over the top on this one. One last question if you don't mind. It seems that the audio is coming out of only one speaker. In the capture options of DVDWS, I have stereo selected. I will play around with the settings and tried to improve upon things. But I'm very happy that I at least can record with sound. Thanks again!

[theDruid]

I'm glad that helped Scuda!

If you're only getting audio on one channel (L or R), I'd suspect it was the cable(s). Make sure they're all plugged in okay - try listening to the playback through the PC without capturing, and play with the jacks where they're plugged in.

There is a balance control on the mixer too - just make sure that's in the centre.

It's worth having a look at the audio in an audio editor.

There are many available - just look in the tools section. Audacity is a good freeware app, and GoldWave is excellent - SoundForge is regarded as the 'PhotoShop' of the audio editors, but it's price reflects that.

You can split the audio from the video stream (and put it back again after you've played about with it) in VirtualDub - assuming that you're capturing to .avi. If you're capturing straight to MPEG (which I think is how the AIW works?), you'd need to demux the audio from the video in something like TMPGEnc or TMPGEnc plus. You may then have to re-encode the audio.

It's certainly worth normalising the audio track (so that it's as loud as it can be without clipping).

cheers,
mcdruid.