View Full Version : Audio questions


Bill Pryor
September 22nd, 2009, 11:11 AM
I've been thinking through whether to shot double system sound or get a Beachtek and go into the camera, assuming Magic Lantern becomes available for the 7D.

But there's one thing that just occurred to me--if you record audio into the camera, how do you check playback since there's no headphone jack on the camera? Will the audio recorded on a CF card play through the Beachtek?

Jon Fairhurst
September 22nd, 2009, 12:03 PM
Hi Bill,

First, you might check these videos out...
1. Canon 5D Mark II Audio Exposed - Boom Mic (juicedLink, Zoom H4n, Microtrack II, BeachTek) on Vimeo (http://vimeo.com/5370880)

One of the advantages to recording directly into the camera is that you can playback in the camera or on an HDMI TV/monitor and review the sound.

The 7D doesn't have an A/V jack, but it has a mini jack. I believe that the camera will include an A/V cable. Hopefully, Magic Lantern will hopefully be able to enable monitoring through this port.

If anybody in the DC area can loan their 7D to Tramm - or if people can pitch into a Tramm 7D fund - that would speed things up.

Bill Pryor
September 22nd, 2009, 12:16 PM
So if there's some kind of headphone (1/4" or 1/8") adapter to that type of cable, we'd have monitoring option then? I read someplace that on the 5DMKII you didn't have any headphone option, but the 7D has this av port, so maybe that's a positive change.

Bill Pryor
September 22nd, 2009, 12:26 PM
Oops, dang. I just found the old thread about the AV port, and I had even posted in it. I've been scouring the web pages for so long and trying to think through all the different things related to shooting video with a DSLR that my brain must have short circuited there. Totally forgot about that discussion.

So, if Magic Lantern gets updated for the 7D, then, with an XLR adapter box of some sort, it becomes reasonable to shoot single system sound with the camera, assuming that Tramm's software to turn off the auto gain works well and comes out in a timely fashion after the camera is shipping. I have to admit, though, that sending an inaudible tone to disable auto gain makes me a little nervous. I listened to one test of the Beachtek 5D box doing that and it didn't work so well, I thought. Does ML eat up one channel when it is used?

Jon Fairhurst
September 22nd, 2009, 02:36 PM
ML sets the input gain directly. You get two separate channels. No tone is necessary.

I expect that the 7D will ship with an AV cable that has a mini plug at one end, and three RCA plugs (yellow, white, red) on the other. A trip to Radio Shack will get you some adapters that go from the RCAs to a stereo 1/8" jack. (I think I had to get two 1/8" F->F adapters, an RCA to 1/8" cable, and one stereo 1/8 F->F adapter.)

I see a couple of good options:
1) buy an H4n or similar and go double system.
2) get a juicedLink and a cheaper recorder. (We have the Microtrack II, which sounds bad on its own, but is transformed by the juicedLink.) Later, you can go single system with the JL. Keep or sell the cheap recorder...

You can also save a tone to an iPod and play it into one of the channels of the 7D through some adapters. I had tried this with the 5D2 using a very high frequency tone, but wasn't happy with the results. By the time I was ready to try more tones, ML was shipping...

Jeff Reagan
September 22nd, 2009, 03:30 PM
if people can pitch into a Tramm 7D fund - that would speed things up.

Can we start such a fund here?

Bill Pryor
September 22nd, 2009, 03:35 PM
I have the older Microtrack I use for voice-overs, and the idea of using a Juicedlink with that is not bad at all. It's OK for voice-over when I can have the mic right in the narrator's face, but it would not be good on its own for dialog. Biggest problem with it, though, is that the thing is nearly worthless for location shooting because of the internal battery you can't replace. It has a shelf life of about a day--have to recharge it the day you want to use it, and I'm lucky to get an hour with it turned on. Mounting it on anything is a problem too.

I'd probably go ahead and get an H4N or Tascam DR-100, unless I see a schedule for when ML might be available for the 7D. It would be nice to have the camera and ML at about the same time and avoid the double system thing entirely.

Matt Newcomb
September 23rd, 2009, 11:52 AM
Can we start such a fund here?

No need, just go to the website, there is a link to donate.

Shaun Walker
September 23rd, 2009, 02:28 PM
Yep :) ... Here is the link:

Magic Lantern Firmware Wiki
Magic Lantern Firmware Wiki (http://magiclantern.wikia.com/wiki/Magic_Lantern_Firmware_Wiki)