The Beachtek Web site claims that their DXA-5D somehow disables the autogain function on the Canon 5D MKII. Really? How is that possible? Anybody have experience with this thing?

It sends a 20K hertz signal to the camera (it's inaudible to the human ear) but the camera hears it as a level and it defeats the auto gain controll, but like I said in another post I'm pretty disappionted with the unit as a whole.

That's ingenious. Wish they had that during my old GL1 days. I do miss that camera despite it's infernal audio issues.

When testing for my video reviews of 5D2 audio, I found that the Beachtek cuts the 5D2 gain, but not all the way. If you give the camera a hot signal, it will cut to a lower gain level and stay there. (This is a camera thing, rather than a Beachtek thing.)

One problem is that the 5D2 autogain is implemented on the digital side. The analog gain is fixed at +31dB, so the recordings have a lot of hiss no matter what you do externally.

If you really want to control the gain, get Magic Lantern. You can set the analog, digital, and monitor levels as needed. If you provide some clean external gain, the sound quality can be very good.

Check out my six part review of 5D2 audio here:
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