View Full Version : Microphone advice needed


Sal C. Martin
February 14th, 2007, 09:48 AM
I have used lavalier microphones with good results but I want to know if others have used shotguns or other dynamic microphones with good results for sitdown interviews.

I have a client who wants three people to do an interview together. I have two lavalier microphones (and could easily purchase a third). But rather than waiting for that whole process, can I use 3 dynamic microphones placed on stands just outside the frame?

I own 3 Electrovoice dynamic stick mics (635). Obviously, I also own a microphone mixer.
Should I consider adding a boom kit to my tools? Which ones work best?

Thanks.

Ervin Farkas
February 14th, 2007, 01:17 PM
Only if you don't care about the quality of the audio. If you do, there is no replacement for a mike placed as close as possible... unless you're willing to pay thousands of dollars for some extra high quality shotgun.

Don Bloom
February 14th, 2007, 01:30 PM
I would either go for the 3rd lav and use your mixer or if you do use the 3 - 635s that you have place them closer than out of th eframe-directly in front of the interviewees would be a good start.
Don

Sal C. Martin
February 14th, 2007, 06:11 PM
Sounds like I am going to buy a 3rd lav. Thanks for the advice.

Will it be wack if I upgrade my lavalier from the first two I have? In other words, if I buy a new Tram lav and use my old Shure lavs will the slight difference in quality make any difference?

Don Bloom
February 14th, 2007, 07:03 PM
IMO I doubt the difference would be that noticable if at all to the typical listener UNLESS the mics you have now really suck so they make the Tram really stand out on its own
(probably not the case though)
Don

Bill Davis
February 14th, 2007, 10:23 PM
Not to complicate things (although when it comes to audio, it's usually REALLY easy to complicate things!) but...

If you're mic'ing SEPARATE people with average spacing around a table or even side by side, you're probably pretty safe.

But you should also be aware if any two of those people are close together, like a interviewer doing a "couple" who are staged so that they're sitting particularly close, you might well run into some of the most common problems of having more than one open mic in an interview - comb filtering and similar phase problems.

This happens when the distance between any TWO open mics and a source - in this case, the mouth of the person talking - get close to equal. The problem is that the source (voice) can arrive at the second mic, with just enough fractional time delay so that certain frequencies of the sounds get mixed together out of phase.

Comb filtering and phase problems are always something to listen for whenever you have multiple mics open in the same scene.

The general rule of thumb is that you want at LEAST three times the distance between the source of any sound and a secondary open mic(s) as you do between the source and the primary mic.

In a sit down interview that's tyically not a problem. If the distance between the mouth and lav of each participant is 18 inches. It's unlikely that any other mic will be anywhere near as close as 18 inches.

However, when people HUG - or when you're inteviewing a couple after a close call in a news situation and they're clinging to each other, a single mic is often MUCH better than two open mics.

Ask the wedding shooters about this. Or better yet, listen to a shoot where someone has put body packs on both bride and groom. You can HEAR the phase mess when they lean in to kiss.

This won't be an issue if you're recording them ISO to their own tracks - cuz you can mute away any conflicts later - but if you're mixing multiple open mics to single camera track, it's something to be aware of.

Hope things work well for you.

Sal C. Martin
February 14th, 2007, 11:24 PM
You guys have some good knowledge!

I might as well ask about wireless lavs. So far I have been using wired mics with good results. But now I want to venture out.

Most of my work is sit down interviews. Is the Senheiser Evolution G2 series (with supplied me-2 shure mic) any good? Or should I save up for the Lectrosonics at more than double the cost? Or maybe I can upgrade the microphone only from the Me-2 to a Tram?

FYI--I have had great results with two shure sm83 wired lavaliers and a shure mixer.

Steve House
February 15th, 2007, 05:42 AM
Bill makes some very valid points about multiple mics open at once. But this is more of a problem if you're mixing on the set. If you record iso tracks from each mic individually you can take care of the mix in post and avoid the interactions by muting all but the speaking track during the mix. Would renting a multitrack recorder like an SD 744 be in your budget for this shoot?

Ty Ford
February 16th, 2007, 05:01 AM
HI BILL DAVIS!!!

Thanks for another "good audio is not trivial" post.

If the OP is thinking, "OK, then, I just use one mic."
BZZZT! You can count on each person speaking at a different level. Bet on it.

If you have a boom op that knows how to "mix in air", he/she may be able to find the right spot, if that's even possible. Other wise you need to boom and mix at the same time.

Regards,

Ty Ford

Sal C. Martin
February 17th, 2007, 03:57 AM
Steve:
For this client, the budget is to mix on the set. Using a multitrack recorder in the future will work well for some of my "high-end" clients.

This shoot is definitely "middle-end" so to speak. I purchased a 3rd wired lav and will mix sources through my Shure field ENG mic mixer. Hopefully the subjects will not be sitting close enough to cause phase problems.

I would love to hear about any experiences from the truly experienced on this forum regarding boom mics and how effective they would be in this situation.

Again, I am looking to branch out and upgrade in the audio department this year.

Thanks.

Ty Ford
February 17th, 2007, 04:52 AM
Steve's right...and "truly experienced." You have, inadvertantly I hope, insulted him with your careless comment.

3 (or more) lavs will be a problem unless the mixer knows the lines and is mixing like a bandit to pull out the mics when they aren't needed and put them back in when they are. A hand tweeked auto mixer might help.

As to the distance between the people speaking (unless they do the hug thing in which sound will suck) that depends entirely on the reflectivity of the set. Letterman and Leno are on a set and although you see lavs, they are often backup for the Fisher Booms being used. Skits on SNL also use Fisher Booms. There is no ceiling. No walls. Very little to bounce audio. Try that in most rooms and it won't work because the walls and ceiling will kill you.

Booms require good boom ops and a mixer.

I'm guessing you don't have a budget for them either.

I don't think you have explained what type of show this is or where you intend to shoot it. Please do.

Ty Ford

Steve House
February 17th, 2007, 06:01 AM
Steve:
For this client, the budget is to mix on the set. Using a multitrack recorder in the future will work well for some of my "high-end" clients.

This shoot is definitely "middle-end" so to speak. I purchased a 3rd wired lav and will mix sources through my Shure field ENG mic mixer. Hopefully the subjects will not be sitting close enough to cause phase problems.

...

If you must mix on-set and have to get all three mics into two recording channels, I'd suggest at least trying to set it up so you're mixing the two mics farthest apart and sending the result to one channel while keeping the mic in the middle on its own iso channel. That way you've got a fighting chance in post. It's enough of a headache to deal with the phase issues involved when mixing two spaced mics picking up the same sound without sticking a third one into the mix.

A day or two rental on a 4-track recorder such as an SD744 isn't all THAT much - Trew's rate card here in Toronto lists it as going for $100 CDN a day, for example. You might also consider recording direct to a laptop as an alternative if you have one with a multi-channel interface, in either case using the audio tracks from the camera as a guide track.

Daniel Epstein
February 17th, 2007, 09:15 AM
Mixing different Lavs can be trouble if they have different patterns. The Tram is very omni-directional while the Shures may not be. Steve's idea of mixing the two outside mics to one track and the middle one to the other track is smart. Two mics open on a track is very acceptable sound if your mixer is of good quality. If one of the people is the host I try to Iso them and mix the guests onto one track. Make sure your mixers pots are quiet so you can adjust them without adding scratchy sound to the track. Also Don't turn the mixed mics all the way off when mixing unless someone is ruining the track by playing with their clothes or something. Another way to deal with this is the automatic mic mixers like the Shure FP-410 which does an amazing job of opening and closing the correct mic in milleseconds. Someone still has to adjust the volume and certain room characteristics can cause problems (like airconditioner on one end of the room). Also it is better to mix mics with the same characteristics with the automatic mixers so the patterns of sound are similar. For three mics it is not that important but four and more it becomes a very practical solution. By the way most of the reality shows were recorded with multiple wireless manually mixed tracks to the cameras before Iso recordings became practical. Most of the time they don't go back to the Iso's. The Wendt X5 is a favorite mixer for many.

Bill Davis
February 17th, 2007, 01:17 PM
Hi right back, Ty.

This is totally off topic, but readers here might get a kick out of it anyway.

A few months back Ty and I did an "iChat AV test" where we took "video tours" of each others studios. It was really fun. When it was over, we logged off and I don't think either of us thought any more about it.

About 2 weeks ago, (I think it was a day after an automatic Apple system update came through including an iChat rev...) suddenly, and quite unexpectedly, I hear Ty's voice coming out of my computer.

Sounded like he was talking to a client. I said "Ty? is that you? He broke off and said "Bill? is that you? Sorry, I can't talk right now... I'm on the phone with a client."

I broke the connection - totally mystefied because I hadn't TRIED to connect with him, somehow our machines discovered we were both "available" for chat and hooked us up without human intervention.

Nothing like this has happend since ... so I'm chalking it up to random cosmic weirdness!

Don't you just LOVE cutting edge technology!

BTW, we DID discover in our original test that you can transfer computer data files including VO clips UNDER an iChat session, - (just to bring this back sorta partially on topic!) so the future of remote VO work looks to be getting easier as tech continues to develop.

Ty Ford
February 18th, 2007, 07:58 AM
Shhh Bill!

No one should know about our Area 42 connection between Scottsdale and Baltimore.

Ty Ford

PS: Let's try that again.