Get low-noise audio with a DSLR and a wireless microphone

The more I do video production with my Nikon D4 DSLR, the more I have come to like how it handles in-camera audio with an external mic attached. One of the big issues with the first generation video-enabled cameras like the Canon 5D Mark II and the Nikon D3s was they had limited audio capabilities. Many producers felt the need to record separate audio into a recorder like a Zoom H4n and then sync it later in post. What a pain. It’s one of the reasons I put off switching from a traditional video camera to a DSLR.

Sennheiser G2 Wireless MicWith my Nikon D3s, I went the route of trying to use a JuicedLink audio interface to manage my audio. The unit bolted on to the base of my camera, which made it feel bulky. It had great features like dual XLR audio inputs, levels monitoring and a headphone jack, but the truth is, on that piece of equipment, I could never dial in a clean audio signal.

A big part of the problem was the way the D3s handled audio with only three levels settings—high, medium and low. The last time I used the camera with the JuicedLink, I had such a high noise floor (a low background hiss) in my interview audio that I just left it on the shelf after that. Soon after, I upgraded to the Nikon D4 and have found I could generate low-noise audio, especially with a wireless mic, all without all the add-on accessories.

I like using a DSLR to shoot formal interviews. The shallow depth-of-field makes the subject look great. I use my trusted Sennheiser G2 wireless mic for my audio. Be advised,  out of the box the gain on these mics are set really high. The first time used it,  I had such distorted audio that it ruined the video story I produced for the newspaper. I quickly learned how to turn down the levels and make them work with my Sony Z1u video camera.

When I first used a wireless mic with My Nikon D4 (plugged directly into the camera’s mic jack,) I found the same high noise floor that my JuicedLink produced. After fooling around with the settings I came to this conclusion: I had to turn the levels on the mic back up and turn the camera audio levels way down. With the right balance (the mic sending the clean signal, which I assume overpowers the camera’s weak pre-amps), I now  get quality audio without a lot noise-floor hiss.

Is my camera audio as good as recording separately to a Zoom H4n? I’d say depends on what you are doing with the video. If its going to be broadcast on TV, or destined for the big screen, then maybe not. But, if you are producing for the Web like I am, I’d say it’s more than good enough.

You can hear an example of what my wireless Nikon D4 audio sounds like in the interview and voiceover audio in this video I produced for a speech therapy clinic:

Here are my settings:

On my Nikon D4 (the same as on the Nikon D800,) I set the camera on manual and dialed the camera audio down to number 4 level.

On the Sennheiser receiver pack (the one that connects to the camera) hit the “Set” button then toggle the left selection button until you get to “AF Out.” Hit “Set” again and toggle the left arrow until you see -12 Db. Hit “Set” again.

Next on the transmitter pack (the one connected to the lav mic) hit “Set” then toggle to “Sensit” and hit “Set” again. Toggle until you get -06 Db. Hit “Set” again.

Now do a test. Watch your in-camera levels. If they are too low, bump up your audio level to “5,” but no more. If they are still too low go back into the mic pack and set the AF Out level to -6 Db.

Just remember that there is no phantom power with DSLRs. You need battery power from the mic for it to work properly. I sometimes put my big Sennheiser ME-60 shotgun mic on top of camera and it works like a charm with very low noise. Just make sure you have a fresh battery in mic and that it is turned on. If you don’t, you won’t record any audio.

One of the great things about the new generation DSLR’s is that they have headphone jacks to monitor your audio. Use it, or you’ll regret it later (trust me on this one.)

Audio Recorder/Preamp Shootout

Robert Rozak, President of JuicedLink, compares and demonstrates the different preamps and digital recording devices for their low noise capabilities . The key information he stresses is that a preamps connected to a DSLR camera are just as good if not better that recording audio separately with say an Zoom H4n. Take a listen and judge for yourself.

Final Cut Pro’s Voice Over Tool is a Time Saver

recordIt took me forever, but I finally tried out Final Cut Pro’s voice over tool yesterday for a daily video I did about a 100 people who lined up at a hardware store to buy snow shovels. The record 60-inches of snow that has fallen in the last month in Spokane, has made snow shovels scarcer then George Bush is on the national scene. 

The voice over recording feature in Final Cut Pro is one I had almost forgotten about. Now that I have started to do more narration in my videos, I realized my present workflow was really inefficient. I had been using an Edirol -R9 digital recorder connected to condenser mic–a Rode NT3.  After recording a script with four or five takes, I would import the audio files into Final Cut via USB from the recorder. It was all very time consuming.

I’m still trying to get the hang of writing a video script.  I usually edit my video in a linear fashion, stopping to add narration when needed. I know this goes against the TV news model of recording the entire script and then quickly laying the b-roll and cutaways on top of the audio. I found the voice over tool is perfect for my editing style.

Here’s how it works. My newspaper bought a cheap USB audio mixer (it cost about $120 bucks) a while ago when we were kind of playing with podcasts. Since we gave that fad up, the mixer was just gathering dust. I rescued it and hooked it up to my Mac. I plugged in my Rode NT3 mic in via XLR cable, turned the power on and was good to go.

In my shovel video story, I would drop some edited b-roll clips on the timeline, then place my play head where I wanted to start my voice over. I went to: Tools>Voice Over to open the voice over tool. It was pretty simple from then on. I clicked the red record button and got a visual and audio countdown before the recording started. It automatically backs the play head up five seconds for the countdown.  I read my short script and when done, hit the space bar to stop recording. The audio clip then appeared in my timeline right where I had placed the play head.  I clicked into the timeline and listened to the clip.  If I hated it, I’d just hit delete it and do another take. 

Some things to remember: You’ll want to make sure you have video clips on the timeline because the voice over tool won’t record on a blank timeline. Also, it won’t record past to end of the last clip or a blank spot between two clips on the timeline.

Update: Peter Saliva adds this even better tip for recording without video on the timeline:

“Another trick you can try when using the voice over tool: set an in and out point in your time line where no media exists, for say 2 minutes. Then you have established a duration in which your voice over can be recorded and you don’t need to have media present. You can record multiple takes without the hassle of muting or disabling additional audio tracks with other media.”

Final Cut Pro’ s voice over tool is going to make doing narration much easier for me.  Now, if I could just learn to write better scripts…