View Full Version : Auto Gain Control in a Dual Record System


Lloyd Ubshura
January 22nd, 2012, 11:49 AM
I need suggestions for audio recording. I know the boards are full of threads, but I haven't found a thread that covers our exact situation. Hope you can help steer us in the right direction.

We currently record a kids show in a 5-cam multi-cam studio environment. We have been using the Sony EX1R for our main multi-cam and using the 7D and 5Dm2 for our "money shots." All the audio has been run into the EX1Rs--done deal, no problem.

Now we are getting rid of the EX1s altogether and going with Canon DSLRs exclusively.

We have played around with our Zoom H4N and have gotten decent results, but it's not a perfect solution for our scenario--at least with our current settings.

The problem is it's a kids show. The kids CONSTANTLY get loud (e.g. laughing) and then very quiet when mumbling. We often record 8 kids at a time--each with a lav mic.

We shoot with the Sony EX1R and run the audio into there and turn on the auto gain control and it would boost the low areas and cap the loud areas. It was working perfectly.

The Zoom's auto controller doesn't work the same way. It seems to cap the loud parts, but never adjusts back up when there's whispering.

I'm looking for an AUTOMATIC gain control solution to our situation that goes UP AND DOWN when needed. I do NOT want 8 audio guys adjusting the gain manually on 8 kids.

80% of our work is studio based, so I don't mind recording directly to a computer through a mixer/limiter of some sort. Not sure if that's an option.

Any suggestions?

Alex Payne
January 22nd, 2012, 09:02 PM
are you actually getting rid of the ex1r's? if you're just not using them anymore, no reason you can't still keep one around to record audio on to.
another option i suppose is to get an adapter and plug directly into the dslr's? Not generally recommended but if you're actually looking for an AGC that might work. Would probably recommend a mixer of some kind as well but do some tests and see what you come up with, might be fine with just the dslr depending on the quality level you'd need.

of course i'm sure there are better options, but those are some ideas to use what you've already got.

Lloyd Ubshura
January 22nd, 2012, 10:14 PM
We are currently only using the EX1s for audio capture. But at $6000 or so a pop, it seems like we have some very expensive audio capturing devices. We feel the money could be better utilized selling the cameras and buying some other system. Even a $1500 system would be a big savings to us.

Al Bergstein
January 23rd, 2012, 02:10 AM
It's sunk cost. I would continue to use the ex1's if they work. Why not?

Derek Reich
January 23rd, 2012, 09:01 AM
Why not just use the 7Ds? They ONLY record audio w/ auto gain. You'd probably be the only person in the world happy about that.

Wayne Avanson
March 1st, 2012, 02:32 PM
There are various compression and limiting settings in the Zoom menus. Not sure if you're tried those?

When I shot a doco in Canada a while ago, the sound guy used various mics through a presonus rack mounted audio interface straight into separate channels on a MacBook Pro. Worked a treat maximum control of levels AND separation. When I got back I bought a Presonus Firestudio Mobile for when I want high quality audio capture, and run it either straight into Logic or Soundtrack Pro on a MacBook Pro.

If you go this route, you can set up a compressor/Limiter insert on each channel's input to control the signal as it is recorded.

Another way is to put a hardware rack mounted multichannel compressor(s) between the miss and the zoom. But that's all getting a tad fiddly.

Hope this helps

Brian Brown
March 6th, 2012, 11:20 PM
Behringer makes some affordable rack-mounted compressor/expander/gates that would work for you. As little as $50/channel. A few of those and a couple of 4-track digital recorders would get you in shape in short order. Of course, it sounds like a lot of wiring... but compared to 8 kids running around, it might even be staid by comparison!