Sound only on one camera at DVinfo.net

Rowan Crosby · June 21st, 2007, 10:45 AM

Hi guys

This is a strange situation that I was wondering if anyone has encountered.

We shot some footage on the HVX onto DV tape using an external mic.

The video and audio plays back fine in camera but when we try to capture it to Premiere Pro only the video is captured, no audio.

Even stranger, when we try to play the tape on another camera, there is no audio.

So basically the audio only plays back on the particular camera we shot it on.

I think it has something to do with the external mic but I'm not sure.

Still new to it all.

Has anyone else come across something like this?

Thanks

Ty Ford · June 21st, 2007, 05:06 PM

If you shot in the 32 kHz 4 ch mode, some decks/cameras can't read that.

Regrds,

Ty Ford

David Ennis · June 21st, 2007, 09:29 PM

Did you check for Left/Right channel cancellation? Some ways of connecting an XLR mic to a stereo input will give you that. If you can hear the audio in headphones, or if you can hear it when you play just one channel in Premier this would be the case.

Rowan Crosby · June 22nd, 2007, 04:28 AM

Cheers Ty

It was recored at 48 kHz and we have tried a few different combos with no luck.

I'll keep trying a few things.
This one has me stumped atm.

Ty Ford · June 22nd, 2007, 04:39 AM

Hey Rowan,

Well there is plain old head alignment. I've heard of tapes that only playback properly in the machine in which they were recorded.

Regards,

Ty Ford

Rowan Crosby · June 23rd, 2007, 06:22 AM

Quote:

Originally Posted by David Ennis

Did you check for Left/Right channel cancellation? Some ways of connecting an XLR mic to a stereo input will give you that. If you can hear the audio in headphones, or if you can hear it when you play just one channel in Premier this would be the case.

Thanks David

I'll investigate this a bit further, sounds like a real possibility.
Would this cause the tape to not play the audio on another camera too?

David Ennis · June 23rd, 2007, 06:45 PM

If this is the problem, then any time the signal is sent to one speaker you get the cancellation. Any time the channels are kept separte and sent to separate speakers you hear it.

It's a common problem when an XLR to 1/8" stereo plug adapter is used to connect a mike. It occurs because there are two types of such cables that are wired differently but look the same.

Rowan Crosby · June 25th, 2007, 01:51 AM

Thanks a heap Ty and David.

It appears to be something along those lines David so I just need to test more thoroughly in future.

Really appreciate all you help guys.

Chris Harris · June 25th, 2007, 03:45 AM

Quote:

Originally Posted by David Ennis

If this is the problem, then any time the signal is sent to one speaker you get the cancellation. Any time the channels are kept separte and sent to separate speakers you hear it.

It's a common problem when an XLR to 1/8" stereo plug adapter is used to connect a mike. It occurs because there are two types of such cables that are wired differently but look the same.

I have this problem using a stereo cable on a mono mic. It's annoying when logging and capturing. Would it be better to use a mono cable?

Ty Ford · June 25th, 2007, 05:37 AM

If the audio would playback in the original camera, I don't think it's a cable problem.

Are you encoding audio into the editing system via analog audio inputs?

Do you not have firewire or USB ransfer capability?

Regards,

Ty Ford

Chris Harris · June 25th, 2007, 03:03 PM

I'm capturing via firewire. It won't play back on the original camera, on any camera, or on any mono speakers, such as my built in Mac Pro speaker. I have to delete a garbage channel in the NLE in order to hear it. I suspect it's that channel cancellation. I was wondering if it could be caused by using a stereo cable instead of a mono cable.

David Ennis · June 25th, 2007, 03:28 PM

Yes, a stereo cable connecting an XLR mono mic to a camcorder's stereo input will give you cancellation every time. It records identical signals with opposite polarities to the two channels. Put on stereo headphones and you'll hear it fine. Play it through a mono speaker and you get silence, or near silence.

Ty Ford · June 25th, 2007, 04:29 PM

Ah, OK that helps.

I you had used a regular XLR mic cable with a regular XLR to mini TRS adapter and plugged it into the analog mini TRS stereo jack on your camera. You would have recorded the positive peaks of the mono audio on the left channel and negative peaks on the right channel.

That's totally different than having one track be of reversed polarity to the other. At least you could pick one of the two and use it.

I'm sort of surprised you didn't hear something was weird when you were recording. That mistake normally sounds like crap, if you get anything at all.

In the future, use a female XLR that sends pin 2 to both the tip and sleeve of the mini TRS plug. That way you send good audio to both channels.

Regards,

Ty Ford

June 21st, 2007, 10:45 AM	#1
Rowan Crosby Tourist Join Date: Jun 2006 Location: Perth Western Australia Posts: 4	Sound only on one camera Hi guys This is a strange situation that I was wondering if anyone has encountered. We shot some footage on the HVX onto DV tape using an external mic. The video and audio plays back fine in camera but when we try to capture it to Premiere Pro only the video is captured, no audio. Even stranger, when we try to play the tape on another camera, there is no audio. So basically the audio only plays back on the particular camera we shot it on. I think it has something to do with the external mic but I'm not sure. Still new to it all. Has anyone else come across something like this? Thanks

June 21st, 2007, 05:06 PM	#2
Ty Ford Inner Circle Join Date: Nov 2004 Location: Baltimore, MD USA Posts: 2,337	If you shot in the 32 kHz 4 ch mode, some decks/cameras can't read that. Regrds, Ty Ford __________________ Ty Ford's Audio Bootcamp Field Guide Ty Ford's Audio Video Blog

June 21st, 2007, 09:29 PM	#3
David Ennis Fred Retread Join Date: Jul 2004 Location: Hartford, CT Posts: 1,227	Did you check for Left/Right channel cancellation? Some ways of connecting an XLR mic to a stereo input will give you that. If you can hear the audio in headphones, or if you can hear it when you play just one channel in Premier this would be the case. __________________ "Nothing in the world can take the place of persistence..." - Calvin Coolidge "My brain is wired to want to know how other things are wired." - Me

June 22nd, 2007, 04:39 AM	#5
Ty Ford Inner Circle Join Date: Nov 2004 Location: Baltimore, MD USA Posts: 2,337	Hey Rowan, Well there is plain old head alignment. I've heard of tapes that only playback properly in the machine in which they were recorded. Regards, Ty Ford __________________ Ty Ford's Audio Bootcamp Field Guide Ty Ford's Audio Video Blog

June 23rd, 2007, 06:45 PM	#7
David Ennis Fred Retread Join Date: Jul 2004 Location: Hartford, CT Posts: 1,227	If this is the problem, then any time the signal is sent to one speaker you get the cancellation. Any time the channels are kept separte and sent to separate speakers you hear it. It's a common problem when an XLR to 1/8" stereo plug adapter is used to connect a mike. It occurs because there are two types of such cables that are wired differently but look the same. __________________ "Nothing in the world can take the place of persistence..." - Calvin Coolidge "My brain is wired to want to know how other things are wired." - Me

June 22nd, 2007, 04:28 AM	#4
Rowan Crosby Tourist Join Date: Jun 2006 Location: Perth Western Australia Posts: 4	Cheers Ty It was recored at 48 kHz and we have tried a few different combos with no luck. I'll keep trying a few things. This one has me stumped atm.

June 25th, 2007, 01:51 AM	#8
Rowan Crosby Tourist Join Date: Jun 2006 Location: Perth Western Australia Posts: 4	Thanks a heap Ty and David. It appears to be something along those lines David so I just need to test more thoroughly in future. Really appreciate all you help guys.

June 25th, 2007, 05:37 AM	#10
Ty Ford Inner Circle Join Date: Nov 2004 Location: Baltimore, MD USA Posts: 2,337	If the audio would playback in the original camera, I don't think it's a cable problem. Are you encoding audio into the editing system via analog audio inputs? Do you not have firewire or USB ransfer capability? Regards, Ty Ford __________________ Ty Ford's Audio Bootcamp Field Guide Ty Ford's Audio Video Blog

June 25th, 2007, 03:03 PM	#11
Chris Harris Major Player Join Date: Mar 2006 Location: San Francisco, California Posts: 487	I'm capturing via firewire. It won't play back on the original camera, on any camera, or on any mono speakers, such as my built in Mac Pro speaker. I have to delete a garbage channel in the NLE in order to hear it. I suspect it's that channel cancellation. I was wondering if it could be caused by using a stereo cable instead of a mono cable.

June 25th, 2007, 03:28 PM	#12
David Ennis Fred Retread Join Date: Jul 2004 Location: Hartford, CT Posts: 1,227	Yes, a stereo cable connecting an XLR mono mic to a camcorder's stereo input will give you cancellation every time. It records identical signals with opposite polarities to the two channels. Put on stereo headphones and you'll hear it fine. Play it through a mono speaker and you get silence, or near silence. __________________ "Nothing in the world can take the place of persistence..." - Calvin Coolidge "My brain is wired to want to know how other things are wired." - Me

June 25th, 2007, 04:29 PM	#13
Ty Ford Inner Circle Join Date: Nov 2004 Location: Baltimore, MD USA Posts: 2,337	Ah, OK that helps. I you had used a regular XLR mic cable with a regular XLR to mini TRS adapter and plugged it into the analog mini TRS stereo jack on your camera. You would have recorded the positive peaks of the mono audio on the left channel and negative peaks on the right channel. That's totally different than having one track be of reversed polarity to the other. At least you could pick one of the two and use it. I'm sort of surprised you didn't hear something was weird when you were recording. That mistake normally sounds like crap, if you get anything at all. In the future, use a female XLR that sends pin 2 to both the tip and sleeve of the mini TRS plug. That way you send good audio to both channels. Regards, Ty Ford __________________ Ty Ford's Audio Bootcamp Field Guide Ty Ford's Audio Video Blog