SD 702 + Zoom H4N

[Brian Maurer]

How do I even start this... please don't laugh?

I've got the SD702, and I'm working for a client that wants to shoot an interview using the EX3 (two XLR inputs). They want everything mono, but indicated they want three mics active. I'm guessing two lavs and a shotgun of sorts (don't understand why, but hey, whatever). The SD 702 has two XLR inputs, and has 2 lines out. But as I said, they want three mics. So, I've got the Zoom H4N as a backup. Now, they want to go directly into the camera, which is also fine, understand their reasoning for wanting to skip that step in post. Was thinking of running the two wireless mics off the zoom, having its 1/8 go to a XLR male into Channel 1 of the mixer. And then use the second channel on the mixer for whatever they want the third mic to do. Does that sound... insane?

[Rick Reineke]

"Was thinking of running the two wireless mics off the zoom, having its 1/8 go to a XLR male into Channel 1 of the mixer. And then use the second channel on the mixer for whatever they want the third mic to do. Does that sound... insane?"
-- Insane? No, not the best routing choice maybe.
The pre amps in the H4n ain't the greatest so... why not feed the mics to your mixer and assign the tracks it to the camera, and external recorder destination from there.

[Jay Massengill]

You should definitely have a more detailed conversation with your client, including their editor, regarding what they are trying to accomplish with the third mic.

I can understand their stated importance of recording directly to the camera, but they also need to understand the potential of uncorrectable damage that is posed by mixing two closely-spaced mics together onto one recording channel.

I would record the two "main" mics to the separate channels of the camera, with the third mic being recorded to one of your external recorders. With a typical long-form interview recording, a simple clapper at the head and tail will help with easily syncing the third mic's separate recording.

As stated, the H4n mic preamps aren't great, especially if the mic doesn't have a hot output. I always feed mine a proper signal from a preamp or mixer rather than connect the mic directly via XLR.

If you don't have a separate preamp or a third channel on a mixer to feed the H4n, I might suggest relying on the camera's recording of the two main mics and use your 702 to record the third mic with greater audio quality and less drift than the H4n can accomplish.

Keep in mind (especially if there is only one camera), the "third" mic could be the interviewer's lavalier mic, dedicating the main lav and backup shotgun or hypercardioid for the interviewee's most important part of the recording. It all depends on what the client really needs to accomplish their goal.

[Brian Maurer]

I agree that a conversation needs to be had with the filmmakers. One thing that greatly confuses me is why they want to have three mics on at the same time, if in fact, they only have one camera and will be shooting only one subject. Perhaps there are going to be multiple subjects in the same shot, but again, if there are two, then there's no need for the third mic. I will be sure to let them know that there's a significant issue with operating three mics onto a single mixed channel. I offered them to download directly off the mixer or the CF card for the SD702, but they seem really dead set on not having to sync in post. I get the feeling that this NPO doesn't have the funds for a bigger post production, and that's why they want a single channel. In fact, I believe they want everything coming into the camera to be mono.

"I would record the two "main" mics to the separate channels of the camera, with the third mic being recorded to one of your external recorders. With a typical long-form interview recording, a simple clapper at the head and tail will help with easily syncing the third mic's separate recording."

I think that's the best way to go, but if they're dead set on directly into the camera, I'll just have to use the setup that I currently have. I tested two mics (NTG-3 / MKH416) going directly into the Zoom, and then using the headphone jack to XLR into the SD, the signal came in strong (gain is actually the volume, in this case). The file came out strong, and the waveform seemed unaffected, without a lot of noise. I just don't really know what they plan to do with that third mic. I appreciate your thoughts as always. I'll report back as to what they're actually doing, just to feed any curiosity here. Thank you both!

[Brian Maurer]

Just as an update, this is what they're planning on doing:

They want to mic both people, in an effort to get a two-shot of both of them. They want the lavs on the two subjects, and then they want the shotgun overhead to serve as a backup, in the event that there's interference from the lavs. I'm going to suggest that the shotgun be used on one channel of the audio of the EX3, and that the two lavs go through the other channel of the EX3. Seems to me that if they're all mixed together, you run the risk of having possible interference or crackling covering all the audio. I assume they can just mix in post. Won't have to be synced. Just balanced.

[Steve House]

Originally Posted by Brian Maurer

Just as an update, this is what they're planning on doing:

They want to mic both people, in an effort to get a two-shot of both of them. They want the lavs on the two subjects, and then they want the shotgun overhead to serve as a backup, in the event that there's interference from the lavs. I'm going to suggest that the shotgun be used on one channel of the audio of the EX3, and that the two lavs go through the other channel of the EX3. Seems to me that if they're all mixed together, you run the risk of having possible interference or crackling covering all the audio. I assume they can just mix in post. Won't have to be synced. Just balanced.

Never try to mix a lav and a boom mic covering the same subject. The sound from the speaker's mouth arrives at the two mics at slightly different times and mixing the two can result in comb filtering distortion. It's better to record the two mics on separate tracks and in post decide which is the better sounding track, then use just that one track for the scene.

Likewise, mixing two lavs down to one channel can give rise to similar problems in some cases. It depends on the positions and spacing of the two subjects - if there's a lot of bleed-over from one subject into the other's mic you could end up with similar comb filtering or reverb artifacts due to arrival time differences. Better to record each lav to its own iso track and mix in post.

Don't know why you're referring to or using the SD702 as a "mixer". Sending the mics to the 702 and then using the recorder's monitor out to send them to the camera or some other recorder just doesn't make any sense to me. If you want to record the lavs in the camera, send them there directly.

I'd put each lav on its own track in the camera and send the boom to an external recorder, your SD702. That way you can checkerboard the tracks in post, muting one subject's track while the other subject is speaking or replace one of the lav tracks with the boom track if needed. Be sure to slate.

The pattern of a shotgun is too narrow to cover two people unless the boom is swung to follow the shifting conversation - your choice with a static shotgun will be either one or the other subject is always off-mic, or both of them are. I don't recall you mentioning if there was going to be a boom operator controlling the mic or if you were going to position it on a fixed boom overhead but it's something to keep in mind. Also a hyper is preferred over a shotgun in most typical interior locations.

[Brian Maurer]

Steve -

I entirely agree with what you are saying. In a perfect world, I'd do just that: put the two lavs on the camera directly, and use the recorder to capture two shotguns (positioned on c-stands --> which I believe will still cause an issue with pickup (shotgun A capturing latent shotgun B)), as backup. It was their idea to have the shotguns as backup, and I can understand that as there are a number of issues with lavs. What's making this a challenge is that the client doesn't want any post-production overhead. I think I'm just going to have to tell them that you cannot mix lavs with a shotgun, and that the safest thing to do, to get the best audio out of this interview is to place the lavs on the EX3, left and right channel (they can balance in post), and use the shotgun as a backup. I'll have to do some research on how to adjust the balance on the EX3 for incoming audio, as I've no experience with that camera. I really do appreciate your advice. I'll bring my slate just in case.

[Steve House]

Originally Posted by Brian Maurer

Steve -

I entirely agree with what you are saying. In a perfect world, I'd do just that: put the two lavs on the camera directly, and use the recorder to capture two shotguns (positioned on c-stands --> which I believe will still cause an issue with pickup (shotgun A capturing latent shotgun B)), as backup. It was their idea to have the shotguns as backup, and I can understand that as there are a number of issues with lavs. What's making this a challenge is that the client doesn't want any post-production overhead. I think I'm just going to have to tell them that you cannot mix lavs with a shotgun, and that the safest thing to do, to get the best audio out of this interview is to place the lavs on the EX3, left and right channel (they can balance in post), and use the shotgun as a backup. I'll have to do some research on how to adjust the balance on the EX3 for incoming audio, as I've no experience with that camera. I really do appreciate your advice. I'll bring my slate just in case.

Sending the lavs to the camera, each on its own channel, is a good example of where a mixer is a useful tool to have in the loop. The mics feed the mixer. Mic 1 is panned full left, mic 2 is panned full right, and the mixer output feeds the camera. Align the mixer output level to the camera with tone, then all further level adjustments ("balancing" as you put it) as the scene proceeds are done using the mixer's input channel faders. Don't try to ride gain on the camera itself as there's enough going on with its controls as it is. Trying to get a usable interview without any post production at all is just not very realistic IMHO and the client needs to be informed of that.