View Full Version : Capturing the 2nd Channel of Audio during Playback - XL1S


Jason Teets
July 20th, 2009, 04:49 PM
I've exhausted pretty much everything I can think of to try to capture the second-channel of audio (a stick mic that went RCA plugs into Audio 2) into Final Cut Express.

The specifics:

I'm using an XL1S.

I recorded interviews at a wedding reception with a wireless stick mic. I had the receiver inputing the signal to Audio 2 via RCA plugs. I switched the Audio Mode from 16bit to 12bit ST-1,2 and switched the Audio 2 input to LINE.

While recording, everything sounded kosher through my headphones (using the Audio Monitor button), and I know the audio is there, because during playback I can also hear the audio through the camera (again using Audio Monitor to sift).

The problem comes when I try to capture those interviews into Final Cut Express. In the clips captured by FCE, the second-channel audio isn't there at all! This prompted me to go into the menu mode while the XL1S was in VCR mode, where I tried just about everything I could imagine there (switching Audio Mode, Selecting Output from L/R, L/L, R/R, L+R/R, and also changing the Audio 2 in the LINE). Through everything I've tried, the clips captured in Final Cut Express continue to go in without ANY sound from Audio 2.

How the hell do I bypass this? Any help is greatly appreciated, and a million thanks goes out to any bloke that gets me on the right track. Really, thanks a million.

- Jason

Chris Soucy
July 21st, 2009, 03:16 AM
Well, this is a complete "Hail Mary" punt, based on a quick flick through both the XL1s and XHA1 manuals.

Seeing as how the XL1s manual seems to deny the existence of computers all together, and simply refers to "other digital devices" and likewise makes no mention (that I can find) of Audio Channels 3/4 appearing anywhere but on the analogue O/P's, I'll put forward a couple of possibilities:

1. The XL1s doesn't actually O/P channels 3/4 via Firewire, you have to rope 'em in off the analogue O/P's

2. It does O/P them via Firewire but your NLE has to know that 4 channels are present and it doesn't.

My bet is option 1 (tho' option 2 has some merit).

Now, as I know squat about FC, I have no idea whether you can ingest via Firewire AND capture from a mic/ line in socket at the same time, but if my reading of the minimalist documentation is within a bulls roar of correct, that's what you're going to have to do (maybe even two passes?).

I'm not going to dig myself too deep a hole here by going into detail on subjects I know pretty well squat diddly about, suffice to say, has that given you a small torch in the darkness?


CS

Jason Teets
July 23rd, 2009, 09:37 AM
Well Chris, you must have a CANON arm (pun intended), because your hail mary pass was well received, for a touchdown!

It was your first thought that rang true. The XL1s (for some reason) doesn't spit the 2nd channel of audio out through firewire. I never considered that it wouldn't. Hmm. Another reason the XL1s is just outdated and quite obsolete.

Anyways, I went analogue out from the section on the back of the camera, and went mini into the Mac. From there I used CD Spin Doctor to record the audio, and then I transfered the file into Final Cut Express.

Thanks again for your help.

- Jason

Chris Soucy
July 23rd, 2009, 03:17 PM
The "age of reason" is not dead!

Think I'll ask the coach for a raise.

Glad to hear you sorted it.


CS

Don Palomaki
July 30th, 2009, 07:20 PM
The XL1 will output AUDIO2 over fire wire if it is present in 12-bit St-1&2 mode, provided the capture software speaks/understands 12-bit 4-channel audio, so the XL1s should as well.

However, many NLE's do not speak/understand/capture 4-channel via firewire. Check the FC documentation and FC user forums. The solution for many people is to obtain capture software that can capture the Audio2 channels. A search on 4-channel capture (and variants on that) should turn up some solutions.

e.g., http://www.dvinfo.net/conf/canon-xl1s-xl1-watchdog/26503-how-do-you-capture-st-2-audio-my-xl1-s-using-fcp.html

Jonathan Jones
August 15th, 2009, 01:42 AM
[QUOTE=Jason Teets;1175455]The XL1s (for some reason) doesn't spit the 2nd channel of audio out through firewire. I never considered that it wouldn't. Hmm. Another reason the XL1s is just outdated and quite obsolete./QUOTE]

Actually, quite the opposite - the ability to record 4 separate channels of audio is a feature that the XL series sports heads and tails above many other makes and models. The inability to capture the additional channels is entirely a limitation of the capturing app.

On the Mac, the standard approach is usually to run a 2nd pass to capture the additional channels (unless you just need the tracks from those channels - in which case only one pass with the properly designated channels active will do the trick.) This can be set up in the capture settings. (otherwise, the default capture settings on most apps is to just capture L/R stereo audio from CH 1 & 2.)

I don't know if FCE has those capture settings options, but that is how it is done in FCP.

You can also designate just those two second channels of incoming audio for importing into Quicktime Pro, Audacity, and other audio recording apps that can access such audio input settings.

Hope this helps.

-Jon

Nathan Gifford
September 15th, 2009, 03:21 PM
Yes you can capture 4 channel audio, DEPENDING ON THE NLE, over firewire. I do it all the time with Cinestream. FCP will certainly do it, and if you are running it on an Apple, it will do it all at once. On Windows machines, it takes two passes.

My guess is that FCE does not support this feature. Vegas Video did if I recall correctly.

The are a number of after market capture programs that will easily allow you to copy itno your program, though I have never used them.

Another thing is that you can use any (at least Canons) miniDV camcorder as a deck. I use a consumer home miniDV as my deck and it is able to read all 4 channels without any problems. I also use these decks as digital audio recorders too, though you will have to sync the audio in post.

One other thing. Capture your audio in 5 minute segments. Some NLEs will have problem with the Canon audio timebase. When you have segments about 10 minutes long you will probably notice the slip. In the final product it will all look normal.

Since you are importing you video by time frames, the only headache is are the extra entries you have to make in the EDL.

Don Palomaki
September 15th, 2009, 03:32 PM
On Windows machines, it takes two passes.

Depends on the Windows NLE (or capture software) you are using. The two I have use mostly do capture all 4 audio tracks if present and so configured; i.e., Fast DV.now AV (obsolete) and Avid Liquid.

Jonathan Jones
September 15th, 2009, 03:57 PM
Yes you can capture 4 channel audio, DEPENDING ON THE NLE, over firewire. I do it all the time with Cinestream. FCP will certainly do it, and if you are running it on an Apple, it will do it all at once.

I think the intended point was not just to be able to capture all 4 channels of audio, but to do it in a way that retains each of them as independent tracks, so that they can be separately mixed, filtered, or otherwise manipulated in post. FCP has always been able to capture all 4 channels (or at least for the last several versions), but to retain them as separate audio tracks, a 2nd pass is still required. (although I can't speak for the audio functionality of FCP 7, I am still using FCP 6.)

From the FCP 6 User Manual - page 302;
"If your DV tape sample rate is 32 kHz and 12 bit: Choose either First 2 channels, Second
2 channels, or Mix 4 channels.
The Mix 4 channels option mixes all four audio tracks into a single stereo pair. "


The only app that I have heard that allows for independent retention of each individual track after a single pass 4 channel firewire DV capture is called Scenealyzer (sp?), and is a Windows-based program.

-Jon

Don Palomaki
September 16th, 2009, 04:23 AM
The discontinued FAST DV.now, which was essentially a capture and file management front end for Premiere 5.x/6.x, captured video as a .DIF file and audio as separate mono .WAV files, 2 or 4 depending on how you set it up and the source material. It was a Windows app.

Nathan Gifford
September 17th, 2009, 07:16 AM
I think you answered your own question. I have no experience with FCP, but in Cinestream I capture a pair at a time, and apply a filter to mask out whatever channel(s) I don't want. If I don't want the video, I just strip it out and delete it.

Now if there is some reason I want only the audio track, I can render it with the filters and then use the rendered audio to replace the original audio.

I am not sure how FCP handles things, but I doubt it is much different than Cinestream. That means your audio track in the NLE have track priority. Basically the tracks closest to the Audio Program has the highest priority (overlays). So if you setup your effects and filters to look at only one track (which is simple anyway) there is no huge reason to want one pure track. Also if there is some reason to want all of the original audio, you have available.

Most of the time, once I apply filters and effects, I am not worried about sequestering audio on any particular track: the effect is the same. Audio rendering is very quick unless I am doing a lot of work with it.