As you may have heard me say before, audio is of the outmost importance when shooting videos. If you look at my two part article on recording audio for video, my preferred way of recording audio is to record it separately on a dedicated audio recorded such as the Zoom H4n, however there are situations when it is more efficient to record the audio straight into the camera.
Recently Canon released a firmware upgrade that allows you to adjust the audio gain control manually and providing better sound control. Additionally, there are a few products out there specifically geared towards helping you get the best sound recorded into your camera. The two most popular products in this category are the BeachTek DXA-5D and the juicedLink DT454. These units trick the ACG within the cameras and provide for much more controlled audio recording. But the also provide means to monitor your audio as well as mixing a couple of channels or audio sources.
I ran a quick and pretty simple test comparing the two units mentioned above as well as recording straight into the Canon EOS 5D MarkII, with ACG enabled and disabled. The location I picked, in front of a noise waterfountain, was deliberate to simulate locations where the ACG tends to perform the worst.
After testing these devices, my preference is still to continue recording on a dedicated audio recorder, but out of the BeachTek and juicedLink units I was most impressed and got the best sound out of the juicedLink DT454. The unit was a little complicated to set up, but once I did, the audio recorded by the camera was the cleanest. The BeachTek came in close, but the juicedLink had a distinctly better audio. Not all is rosy with the juicedLink though, the way this unit gets such clean sound is by feeding the camera a reference signal over one of the audio channels which in essence forces the camera into a constant gain level, which means all your audio is recorded on only one channel, the left channel; the right channel contains some white noise.
The juicedLink has 4 audio channel inputs, including 2 XLR all of which you can adjust the audio levels to get as clean as sound as possible. As mentioned before you can also monitor the sound, which is crucial to make sure you are capturing the right audio. So if you need to record your audio “in camera” I would HIGHLY recommend the juicedLink DT454.