Capturing Four Channel Audio via Firewire
 

I have been shooting with the onboard mic recording to Stereo 1 L+R, and a shotgun mono to stereo 2 L. Test captures via firewire to various capture programs seems to only access stereo 1.


Addendum: I just discovered the article at http://www.dvinfo.net/canon/articles/article67.htm which seems to state that this issue is hardware dependant. As per my notes/questions below, if I understand firewire 'capture' directly, shouldn't the four tracks be on my HD now, accessible to the right application?


Notes:

Note 1. If I understand the firewire av protocol correctly, the video and audio is being pulled in exactly as it is on tape, meaning (PLEASE confirm or correct this supposition) all four audio tracks should be on HD in the AVI wrapped DV.

Note 2. I'm 'capturing' (wrapping) the DV in AVI Type 2 format. When I import these files in Premiere, I find that it shows up as 16 bit stereo audio (stereo 1 only) not 12 bit. I have the correct project settings specified in premiere.


Questions:

Q1. Am I right in assuming that all four tracks are being pulled in via fire wire?

Q2. Should I be using Type 1?

Q3. Is it a shortcoming of premiere?

Q4. Is there an alternative editing application that will detect and rip the audio tracks out as wav files?


I refuse to just analog capture. I'm using DV for the quality, and I know there is a way to solve this!

-Ethan, Hong Kong

Sorry but I do not know your answers, but in FCP, I've seen that you can choose capture prefs. Also, when you start a project, you have to specify 12 or 16 bit. Perhaps you are in 16 (so it only offers L or R of channel 1)whereas you should start in 12?

Channel 1 stereo
Channel 2 stereo
mix (all four)

I have not seen the ability to get, for instance, all four isolated channels. The mix thing bugs me to no end. I don't even think it's a choice of balance for that mix. So it appears as though if I want full control, I'm going to have to capture things twice; once for Channels 1 and then for 2... :o( Then again, maybe I should look at my original prefs, too?

If any one knows different I'd like to know.

This may be getting off XL1s specific topics... Chris maybe you'll have to move this discussion if that's the case.

Regarding the capture prefs, Premiere does have a 12 bit option when setting up a dv project. I'm using that, but I think the problem is in the avi 'wrapping' stage during capture.

When writing a type 2 dv avi file, the audio is laid on to the DV a/v stream as another audio stream. If I understand what is happening correctly, this is upconverted to 16 bit at that stage.

This is probably why the article in my posting above mentions that four channel audio is captured by some systems as one avi plus one wav file. If type 2 avi files can only handle one 'extra' stereo audio track in the avi, then it has to write the other audio channels out to a wav file, likely also upconverted to 16bit.

One other note. The mix options in the XL1s setup menu has no impact when capturing DV via firewire (again, if I am understanding this correctly).

-Ethan, Hong Kong

We use 4-channel audio all the time. Just make sure you do the following:

1) In the camera, make sure it is set up for Stereo 1+2 and set the proper settings for each.

2) In the editing program, specify whether you wish to capture Stereo 1 or Stereo 2. If, for some reason, you really need to capture both, you will need to capture the footage twice - once for Stereo 1 and once for Stereo 2. (A rare exception to this case - you may be able to find a program that will capture video + Stereo 1 in the main movie file and Stereo 2 in a separate wav file. However, I believe it still captures twice.)

Using Cinestream, for example, whether you choose to create a 32k project or a 48k project, you can easily specify which channels you wish to capture including:
Stereo 1 L + R
Stereo 1 L only
Stereo 1 R only
Stereo 2 L + R
Stereo 2 L only
Stereo 2 R only
No Audio
(Unfortunately there is no Audio Only setting)

Edward

Depending on the package, capture twice.
 

I am not sure which packages capture all four tracks at the same time, but some do not.

Since everything is on t/c it is an easy task to go back and capture again. Even if Premiere is capturing in 16 bit, your audio is only 12 bit because that was the way you recorded it. You just copy the t/c settings from the desired segment into a duplicate, select the other audio track and load it into batch capture. Crank it up and go for tea.

When I have all four tracks, in CineStream, I just lock the segments together and blow away the video from one of the other segments. That way editing I do to the length of video or audio propagates to the other audio tracks keeping everything in sync.

Frankly, its faster to do that it is to write about.

Happy Mardi Gras,
Nathan Gifford

Capturing all four audio tracks is in part a function of the capture software and its drivers. I use DV.now AV which can be set up to capture all four tracks from firewire very nicely, and it saves them to .WAV files on disk for easy sweetening/editing.

Yes, but not all packages can.
 

dpalomaki,
Yes you are right, some packages do capture all 4-tracks in one pass. However, it is important that newbies know that not all packages support 4 track. For example, Vegas Video will not capture 4-track.

Nathan Gifford

Canopus cards from the Raptor on upward will capture 4 channels if Canopus Edit software is used. Their website has PDF manuals for Canopus Edit showing the menu option to enable 4-channel capturing.

What I'm reading is suggests that, since no option to capture the stereo 2 tracks exists in premiere, that I should explore other capture software.

However, I must emphasize that I am pulling in DV via a "simple" OHCI compliant firewire port, not a dedicated HW solution like canopus. However as it is _the_ standard type of port to use dv over, I assume that using a solution like DV.now AV or Cinestream will solve this problem.

I'm quite surprised that Premiere 6.0 doesn't fully support four track DV. Does anyone have any real experience with four track in dv capture in premiere?

I also want to emphasize that I'm not going out to buy a new HW card. I am very pleased with the performance and simplicity of my laptop based solution, so really want to solve this in SW.

-Ethan, Hong Kong

I appreciate everyone's input, but the resulting comments still elave much grey area.

After some more research, it would seem that ALL systems that are capturing four track audio are *hardware based*.

Anyone with clear information to the contrary?

I HAVE FOUND A SOLUTION!

There is an answer. I will post more info after I finish testing this weekend...

It probably is purely software drivers. As noted the DV.now capture drivers do capture 4-channel audio, if set to do so. The firewire port on their card is a standard TI 1394 interface (WIN even attempts to install the TI driver). With the DV.now (Dazzle/FAST) driver installd, Premiere lists an optionot capture auido channels 1-4. However, I have not tried 4-channel capture from within Premiere.