View Full Version : Ready-made AGC-defeater?


Ken Hull
September 15th, 2010, 12:29 PM
So I told my boss that a few months ago I had seen a product announcement of an inexpensive device that could disable the AGC in the company's Sony consumer camcorders. Our audio signal is coming from the headphone output of a mixer, and going into the mic input of the camcorder. I've been searching the internet for that device, and I'm beginning to think this was just "wishful remembering". Searching the forum here, I see many posts by people who've made their own AGC-defeater, using an MP3 player and a Y-cable. Before I tell my boss he'll have to build his own, has anyone seen an off-the-shelf device to disable AGC?

(I've read about the JuicedLink DN101. A bit pricey, and I don't know if it would work without the JuicedLink XLR adapter.)

Ken

Jay Massengill
September 15th, 2010, 03:27 PM
I don't currently use a camera that has auto-only level control, so I don't have a direct answer to your primary question.
However, I will ask why a headphone output from a mixer is being used to feed the mic-level input of a camera?? There are much better ways to do this.
I'll also say there are many prosumer video camera models available that do have manual audio level controls.
I would be more inclined to recommend a camera with manual audio (unless we're talking about a dSLR, in which case the choices are much more limited), before I would recommend an attempt to defeat the AGC with something less effective than a Juiced-Link.
If this is a business use, rather than just a hobby, there are reasons why the proper gear costs more and why those qualities are important to the end results.
Sure, we've all experimented with shortcuts that are cheap, but I don't recommend it for anything above hobby level.

Chris Barcellos
September 15th, 2010, 04:23 PM
Check out Juice Link

JL-DN101 [JL-DN101] - $139.00 : juicedLink, Unique and Trusted Solutions for Audio and Video Production (http://www.juicedlink.com/audio-preamps-mixers-etc/product-list/jl-dn101)

BeachTek DXA-SLR Active DSLR Adapter (http://www.beachtek.com/dxaslr.html)

Andrew Smith
September 16th, 2010, 06:38 AM
Definitely the Juiced Link.

BTW, when people say that something is a bit pricey, my response is ... "compared to what?"

Andrew

Rick Reineke
September 16th, 2010, 08:50 AM
I would investigate if the Juice Link would 'disable' the AGC on your specific camera.
There are some different AGC circuit designs used by other manufacturers.

Ken Hull
September 16th, 2010, 11:46 AM
Thanks for the helpful input guys.
Well, it looks like I tell my boss it's JuicedLink or build-your-own.

Ken

John Willett
September 17th, 2010, 01:51 AM
Definitely the Juiced Link.

BTW, when people say that something is a bit pricey, my response is ... "compared to what?"

Andrew

Yes - I clicked the Juiced Link link and thought it was extremely cheap.

So cheap that it's almost too cheap.

If you think it's pricey I dread to think what other equipment you have been using.

Steve House
September 17th, 2010, 04:44 AM
Note that the DN101 only works when paired with a Juicedlink mixer - it's only an add-on to add the AGC killer and metering to an existing mixer and does not include the core audio circuitry such as preamps etc found in the full product.