Stereo Audio Captures in mono

Furthercom wrote on 3/6/2004, 8:16 AM
I have one group of shots that are recorded in stereo (using a handheld mic in one channel and the on camera mic in the other). When I capture these clips they digitize as mono. There are other shots on the tape, but they digitize correctly in stereo. What could be the proble with these clips? Is it something I could have inadvertently clicked in the capture window, or something on the tape. The tape is showing the two independant levels for each channel so I can see the audio is stereo on the tape.

Comments

farss wrote on 3/6/2004, 8:22 AM
Well for starters capturing doesn't involve any digitising, assuming you're coming off DV via 1394. What ends up on the HD is what was recorded on the tape, period.

So what are you seeing on the audio on the TL?
If it's mono then there'll be only one waveform or have you flicked one of the channel switches. Even if you only record audio on one channel you still get both of then in Vegas, just one channel has nothing in it.
Furthercom wrote on 3/6/2004, 9:10 AM
I see only one waveform and it contains both sounds (the handheld mic and the on-camera mic). I'm sorry about calling it digitizing, I am capturing via 1394. It has always worked perfectly. This is the only instance where I have had this problem. Any ideas what I could have done wrong to make this happen? Even if I try to re capture these clips they still come over as mixed mono.
Zulqar-Cheema wrote on 3/6/2004, 1:38 PM
Ah, I can have a good guess on this as I had this with my camera doing the same as you, using a Sony VX9000.
if I set a switch to Duel, I would only get one channel when I captured, this a radio Mic on one channel and a rifle on the other. I was told by Sonic Foundry that a flag is raised in the fire wire stream and this says two mono channels (and not a pair for stereo) and V4 will only capture on of the channels, was not told why.
The other though that comes to mind is you are getting the same but one of your channels has both microphones on one channel, giving the impression you are only capturing in mono.

I have had to stop using the dual setting on my camera (a bit of a pain) and use a microphone splitter lead to feed two mono mic's in to a stereo socket
Furthercom wrote on 3/6/2004, 7:27 PM
This is very interesting. I was using a DCR 200. It has two XLR inputs in the back. I used channel one for the camera mic (using a switch on the side of the camera. and on channel two, I plugged in the XLR cable from the handheld mic. Is it really possible that Vegas, (or the DV firewire) "flags" the audio as being separate mono signals and then only send one (or the both)? Anyone know any more about this? What is I had very different things on each channel, such as Music on one channnel and narration on the other?
jetdv wrote on 3/6/2004, 7:48 PM
To capture your 4-channel audio tapes, use Scenalzyer Live as your capture tool. In your case, it sounds like you will get two separate mono feeds.
Caruso wrote on 3/6/2004, 8:52 PM
What happens if you plub stereo headphones into your cam while playing back the source tape? Does the audio playback, one channel to the left earphone and one to the right?

If so, I'd just capture the audio separately through your sound card, then, discard or mute the audio that is captured through the firewire. Import the analog stereo audio that you captured through the sound card, place it on the Vegas timeline, sync it with the video.

I have an older Sony prosumer cam that lays down both a mono audio track along with a PCM stereo track on an 8mm tape. If I capture that tape by playing back on a digital 8 camcorder, only the mono track gets captured (as two stereo tracks, but both exact copies of each other).

To get around that problem, I just capture the audio separately.

Your problem sounds to have a different cause, and I agree that it sounds wierd that Vegas would be thrown off because of the separate mic setup that you describe - sounds wierd, but not impossible.

Good luck - hope this helps.

Caruso
miwi21 wrote on 3/6/2004, 9:43 PM
I’m having trouble in this regard as well. My Sony PD-X10 shows audio as being stereo on the meters, sounds stereo through the headphones. I have tried the on-board stereo mic, a stereo mini-plug mic, stereo mic in through XLR’s.

The audio is captured as mono both from tape output and direct from camera(live shot).

Hope there is some fix for this.
farss wrote on 3/6/2004, 10:50 PM
This is pretty wierd, I've captured hours of dual mono off SP via ADVC-300 and not single problem. Cannot see how that's different to capturing from a camera tape unless you've got the camera recording 12bit / 4 track audio.
Zulqar-Cheema wrote on 3/7/2004, 2:54 PM
As I said in my previous Post I can capture two mono channels, IF I do not flick the Dual switch on the camera which then adds a flag, to say 2 mono tracks. The ADVC is just seeing a stand FW signal with no flag raised and so captures the two channels regardless of the content in each channel.

I also guess with the DSR200 (A VX9000 in DVCAM format) you should not have a problem with the two XLR's unless you also flick that switch on the side.
The idea of the dual switch is a good one as it lets you plug in an external Mic and still use the internal one as well, both on different channels.
miwi21 wrote on 3/7/2004, 3:32 PM
As I said, video from my PD-X10 captures as mono. I note that the audio
level bars in camera seem to indicate stereo and the output through
headphones sounds stereo, but it captures as a mono file. Both from
tape and a "live camera shot".

I've tried capturing into two different computers with same result.

I used tape created with PD-X10 and captured using VX-2000 and PD-150
and it captures as mono.

My Digital 8, VX-2000 and PD 150 all capture as stereo.

With the PD-X10 I tried using the on board stereo mic, a stereo
mini-plug mic(Sony MS908?), and a stereo mic through XLR inputs(Senn
MKE44P), all capture as mono.

The only qualifier to all of this is that if I change the audio
settings to the inferior 32k then it will capture as stereo, go back
to 48k and it captures mono.

I'm sure I have the "dual" switch set correctly, and it shouldn't make a difference when using the on-board stereo mic or stereo mini-plug mic.
Zulqar-Cheema wrote on 3/8/2004, 4:31 PM
I am guessing here. If you have recorded footage on the PD-X10 then if played on other machines the flag (if it is that) would still be there as it is in the video stream. The possibility of some form of fault or bug in the PD-X10, one way would be to try a different machine and see if it does the same.

if you have tried to capture using V4 in other PC's and you get the same result then that says the flag is there, i would check the manual or do a search on a PD-X10 site of there is one. Sorry i can be of no further help on this.

Odd about the 32k being OK, perhaps they figure if you use that setting you are using the int Mic and at 48k the ext Mic so will be two mono tracks.