Best boundary mic for interviews with multiple participants?

[ctweiner]

Hi, I've been reading the posts here on boundary mics, and they've been incredibly helpful. But...my purposes are a bit different: I'm looking for a good mic to do interviews with. The interviews involve 2-3 ppl max, sitting about 5 feet apart. The PZM 185 is an option (nothing over $200), or Shure MX393/0 or, for half the price, the Propoint boundary mic. My needs don't involve a stage or musical instruments, so I'm not sure what would work best. I also don't know anything about phantom power or whether I want it. I just want easy, portable and quality.

So far, I've tried the mic in the camera (Canon FS 11), which isn't bad, but I'd like a bit more audible language with less interference from the HVAC. I also tried a shotgun mic, but I, the interviewer, wasn't audible enough. Then I got a lavalier mic for the interviewee and dealt with the fact that one person sounded less audible. So far, that's been the best. If I used it again, I would place it farther from the speaker bc you could hear his every sniff. I also bought a mixer,but for $450, it's too much trouble and only allows for 2 ppl. Which is why I thought a boundary mic would be better. Any input would be appreciated.

Thank you.

 

[Footer]

Boundary mics are not really the way to go for recording. They are meant for low profile situations where you want a microphone that is invisible but provide some pickup. I would go with a high quality condenser such as the SM81 or AKG 451. Keep it just out of frame and you should be set. Both of these mics require phantom power. Now, loud HVAC is going to be picked up by most mics regardless. If it is a serious problem, lav mics for each person and a small mixer is going to be your best bet.

 

[ctweiner]

Thanks for the suggestions. The two condenser mics you mentioned are pricey for me. I can spend $400 or so, but I would prefer to spend under $200. Most of the reviews on B and H that I've read talk about condenser for music...But I'll look into it.

 

[FMEng]

Actually, the PZM would work reasonably well, especially if the interviewees are seated at a table. The key is to try and arrange the people so that they are equal distances to the mic and as close to it as practical. An omni in a fixed location wouldn't have any advantages over the PZM unless the source to mic distance is reduced, but the PZM would be free of boundary reflections and the resulting comb filtering.

There are only two ways to reduce the HVAC noise with a single mic. One is to reduce the source to mic distance, and the other is to use a directional mic, like a shotgun on a boom. In order to accomplish either of those, you would need a boom operator. If you can handle multiple mics, lavs and a mixer would reduce the noise. This is why on almost any professional film set you will see a boom operator and a shotgun mic. Or, they'll have lavs managed by a person mixing.

The 81 and 451 are great mics, but any high output omni will do the job. We're not micing pianos or drums here so they are a bit of overkill. Take a look at the Crown Sound Grabber II. At under $100, you can hardly go wrong.

 

[ctweiner]

Hadn't thought of shotgun on a boom. I'll take a look at the Crown Sound Grabber II. The bad reviews complain of precisely what I want: too close of a range. I'm really trying to avoid lavs and a mixer. Thx!

 

[museav]

The Sound Grabber II and the PZM-185 are very similar but with the Sound Grabber having an unusually high output impedance. Both of those require an internal battery rather than phantom power, which means having to keep up with and change batteries but the alternative is to consider how you would provide phantom power. External phantom power supplies are available, but it sounds like would push the budget.

A boundary mic is going to pick up what it gets. You have no way of controlling each individual's level other than by moving the microphone closer or further away and a boundary microphone at the same distance from all of the people speaking may not be desired unless all of the people speak at the same level. To pick up all the talkers equally it would have to be an omni mic, which would then also pick up everything else in the room.

A shotgun may have difficulty picking up all the participants unless it is further away, which somewhat defeats the purpose. And it may not reduce HVAC noise as much as you think unless that noise is coming from a direction that it can reject while still picking up the talkers. Where it makes the most sense is where you can have someone responsible for moving the microphone to focus on one individual at a time.

If you can't afford multiple mics and a mixer for them that is one thing, but if operating a simple mixer is considered too much trouble then maybe that is an indicator that the sound quality isn't really that high of a priority. The only way to be able to control the relative levels of the individuals is to have a mic for each participant along with a mixer, which could also provide phantom power. This is why little mixers like the Shure FP33, SCM268 and SCM410 are so popular but even a small Behringer or Mackie type mixer would allow level control of the individuals and some EQ to help with noise and sound quality.

 

[ctweiner]

I plan to do another 20 interviews or so with the majority consisting of me and one other person. I have to sit by the camera to remind the person to look at the camera, and sometimes s/he looks at me. The mic needs to be in between us: if the person is too loud or soft, I can adjust my own voice. Plus I can move the mic closer or farther from myself. I would say this is THE advantage to not using the internal mic in the camera. Even with three ppl, I can move the mic away from the loudest speaker. I don't mind batteries (as long as there's an indicator light), so phantom power won't be necessary.

I can afford mics and a mixer-- but you are right, I didn't think the slight difference in sound was worth the money or trouble. With the $40 audiotechnica lavs, the sound is excessively clear, and I don't feel it's all that important to hear my own voice as perfectly as the interviewee. I just ask questions every so often. I also never tried out the field mixer bc in addition to batteries and adapters, I needed an XLR cable, which the store didn't have in stock. I'm looking for simple, but better than the internal mic. The problem is that if I end up wanting to publish this material, I'll have to reshoot everything... Anyway, thanks for your sound logic. Right now I'm thinking about the Soung Grabber, finding a room with no HVAC and limited background noise, but possibly after I speak to my advisor, I'll reconsider the mixer and lavs, who knows.

 

[howlingwolf487]

"ct",

When I did ENG shoots (news interviews), I found that by framing the interviewee and standing with my head to the side of the lens allowed us to talk naturally while giving the appearance of them looking into the camera. I would either hold the interview mic or clip it on them myself and would be able to clearly hear myself in the room mic asking the questions.

This may or may not work well in your situation. When you say you interview 2-3 people at a table, how are you framing them? I assume the camera is on a tripod - are you operating it? If so, who is asking the questions? I see no reason why you can't conduct interviews one-on-one with the equipment and crew you currently have available. You either need to upgrade gear or upgrade your crew...I vote for adding another person to pull the weight.

 

[ctweiner]

That's EXACTLY what I've been doing. I clipped one lav (audiotechnica 3350) onto the interviewee and I sat by the camera and asked questions. That, so far, has produced the best results. If I place the lav low on the person with the mic facing out towards me, it's the most effective. My voice sounds a tad distant, thus my questions probing for better quality. I operate the tripod, and by operate, I mean I frame the speakers, nothing more. 3 feet or so from the camera. Sometimes I interview couples, so the lav has to pick up all three voices. We're not always sitting at a table, but I can find a table to sit the mic on if need be. If that Sound Grabber really needs a flat surface for sound to bounce, I may not get it (still working to figure it out). I go into schools, people's homes, wherever, with no control over my surroundings.

I am obviously a novice and would prefer to spend my budget on paying my interviewees rather than equipment, but I want reasonably professional quality. Everyone gives me advice, but none of them know as much as the contributors to this site. I'm glad to know my make-shift method isn't so crazy, but I'm still exploring.