Capturing stereo pair with FCP 4 HD at DVinfo.net

Erik Polta · June 12th, 2004, 11:31 AM

Hello,

I'm using a Canon GL-2 with an Azden SGM-1x mic, connected to the camera with an xlr to stereo mini connector. When I log and capture the footage using FCP 4 I can hear the audio captured with the Azden fine. Once the clips are in the browser I double click on them for editing and the audio levels are so low audio can't be heard. If I drag the clips to the timeline and make them a stereo pair the levels are fine and I can hear the audio again.
Two questions:

Can I capture the audio as a stereo pair instead of mono a1/a2 so they don't have to be converted to a stereo pair in the timeline?

Why do I have to do this? When I capture clips with the onboard mic the sound the levels are fine?
thanks for your advice - the workaround is o.k. but time consuming!
Erik Polta

Jeff Donald · June 12th, 2004, 02:06 PM

Do the audio meters in FCP also reflect low levels? Are you capturing the audio in FCP at the correct bit depth (12-bit or 16 bit?) and the correct frequency (48KHz, 44.1 KHz, 32KHz?) FCP will only capture two audio tracks in a pass. If you're trying to capture 4 channels, you'll need to do two passes.

Erik Polta · June 12th, 2004, 05:56 PM

Jeff,

Thanks for the reply:

Here's whats happening: When I click on the clip in the browser to load it into the viewer it plays back with no audio - the audio meter is registering audio (it moves up and down) but they are centered around -60 db.
When I drag that same clip from the viewer to the timeline and play it back in the canvas the audio is still hovering around -60db. When I click on the clip and tell it to be a stereo pair the audio will jump (upon pressing play again) back to the normal range - around -12 db.
This same behavior is absent when I capture using the onboard GL-2 mic.
I believe I'm capturing at 16bit - 48 Khz for both the onboard mic and the azden (same preset setup) Any ideas?

Jeff Donald · June 12th, 2004, 06:05 PM

If you're capturing 4 channels of audio, it's not 16 bit. The bit depth for 4 channel audio is 12 bit, 32KHz. Your capture settings need to be adjusted accordingly. If you're trying to maintain some kind of stereo presence you'll need to pan your channels.

Erik Polta · June 13th, 2004, 09:11 PM

Jeff,

thanks again for the follow up!
I'm actually only capturing 2 channels at a time. As far as I can tell the two mono tracks are the ones being recorded by the azden. It seems that when the Azden is plugged in, it takes priority and disables the onboard mic - therefore the two mono tracks (a1, a2) are in fact from the azden - and they are set to record at 16bit 48khz.

Jeff Donald · June 13th, 2004, 09:20 PM

If you have your sequences set up the same as the recorded audio, then I'd try trashing the preferences. Instructions are at the top of the forum in the first post. Please post back if it works.

Erik Polta · June 18th, 2004, 07:17 PM

Jeff,

thanks for the follow-up. It appears no matter what I do the problem persists. If I pan both mono tracks in the viewer to -1 and +1 I can get the audio to acceptable levels. If I drag the clip to the timeline and make it a stereo pair, the panning is done automatically in the process and the problem is fixed that way also.
Both techniques are acceptable workarounds, but they are exactly that - a workaround. What I'd like to be able to do is have the levels correct straight from the import - like they are when I use the onboard mic. Or, if I could somehow capture the audio as a stereo pair by default? I'm just about out of ideas, but I sure welcome anyone who might have some insight.
thanks again
Erik Polta

June 12th, 2004, 11:31 AM	#1
Erik Polta Tourist Join Date: May 2003 Location: Little Rock AR Posts: 4	Capturing stereo pair with FCP 4 HD Hello, I'm using a Canon GL-2 with an Azden SGM-1x mic, connected to the camera with an xlr to stereo mini connector. When I log and capture the footage using FCP 4 I can hear the audio captured with the Azden fine. Once the clips are in the browser I double click on them for editing and the audio levels are so low audio can't be heard. If I drag the clips to the timeline and make them a stereo pair the levels are fine and I can hear the audio again. Two questions: Can I capture the audio as a stereo pair instead of mono a1/a2 so they don't have to be converted to a stereo pair in the timeline? Why do I have to do this? When I capture clips with the onboard mic the sound the levels are fine? thanks for your advice - the workaround is o.k. but time consuming! Erik Polta

June 12th, 2004, 02:06 PM	#2
Jeff Donald Warden Join Date: Mar 2002 Location: Clearwater, FL Posts: 8,287	Do the audio meters in FCP also reflect low levels? Are you capturing the audio in FCP at the correct bit depth (12-bit or 16 bit?) and the correct frequency (48KHz, 44.1 KHz, 32KHz?) FCP will only capture two audio tracks in a pass. If you're trying to capture 4 channels, you'll need to do two passes. __________________ Jeff Donald Carpe Diem Search DVinfo.net for quick answers \| Where to Buy? From the best in the business: DVinfo.net sponsors

June 12th, 2004, 06:05 PM	#4
Jeff Donald Warden Join Date: Mar 2002 Location: Clearwater, FL Posts: 8,287	If you're capturing 4 channels of audio, it's not 16 bit. The bit depth for 4 channel audio is 12 bit, 32KHz. Your capture settings need to be adjusted accordingly. If you're trying to maintain some kind of stereo presence you'll need to pan your channels. __________________ Jeff Donald Carpe Diem Search DVinfo.net for quick answers \| Where to Buy? From the best in the business: DVinfo.net sponsors

June 13th, 2004, 09:20 PM	#6
Jeff Donald Warden Join Date: Mar 2002 Location: Clearwater, FL Posts: 8,287	If you have your sequences set up the same as the recorded audio, then I'd try trashing the preferences. Instructions are at the top of the forum in the first post. Please post back if it works. __________________ Jeff Donald Carpe Diem Search DVinfo.net for quick answers \| Where to Buy? From the best in the business: DVinfo.net sponsors

June 12th, 2004, 05:56 PM	#3
Erik Polta Tourist Join Date: May 2003 Location: Little Rock AR Posts: 4	Jeff, Thanks for the reply: Here's whats happening: When I click on the clip in the browser to load it into the viewer it plays back with no audio - the audio meter is registering audio (it moves up and down) but they are centered around -60 db. When I drag that same clip from the viewer to the timeline and play it back in the canvas the audio is still hovering around -60db. When I click on the clip and tell it to be a stereo pair the audio will jump (upon pressing play again) back to the normal range - around -12 db. This same behavior is absent when I capture using the onboard GL-2 mic. I believe I'm capturing at 16bit - 48 Khz for both the onboard mic and the azden (same preset setup) Any ideas?

June 13th, 2004, 09:11 PM	#5
Erik Polta Tourist Join Date: May 2003 Location: Little Rock AR Posts: 4	Jeff, thanks again for the follow up! I'm actually only capturing 2 channels at a time. As far as I can tell the two mono tracks are the ones being recorded by the azden. It seems that when the Azden is plugged in, it takes priority and disables the onboard mic - therefore the two mono tracks (a1, a2) are in fact from the azden - and they are set to record at 16bit 48khz.

June 18th, 2004, 07:17 PM	#7
Erik Polta Tourist Join Date: May 2003 Location: Little Rock AR Posts: 4	Jeff, thanks for the follow-up. It appears no matter what I do the problem persists. If I pan both mono tracks in the viewer to -1 and +1 I can get the audio to acceptable levels. If I drag the clip to the timeline and make it a stereo pair, the panning is done automatically in the process and the problem is fixed that way also. Both techniques are acceptable workarounds, but they are exactly that - a workaround. What I'd like to be able to do is have the levels correct straight from the import - like they are when I use the onboard mic. Or, if I could somehow capture the audio as a stereo pair by default? I'm just about out of ideas, but I sure welcome anyone who might have some insight. thanks again Erik Polta