Large diaphragm condenser as boom mic?

Marc André Bolduc

Marc André Bolduc

Member
Hey guys! I tried to search the entire web to find answers but I found nothing. Is using a large diaphragm cardoid condenser microphone on a boom a good idea? It seems like nobody does it but to me it sounds like it would work just as good as a small diaphragm pencil mic. Is it just a convention or is there any important reason why it's not done?
 
There are lots of people who put large-diameter condenser mics ("LDC") on booms. But they tend to be in a recording studio tracking music.
We must assume however, since you are in this website, that you are referring to picking up dialog for video/film production.

The reasons it is not done (or even much discussed as you have discovered) include (but not limited to)....
1) LDC are big. They are more difficult to keep out of the frame of the shot than smaller mics.
2) LDC are heavy. You would need to hire weightlifters to wield booms using LDC mics. Weightlifters who were also good at audio.
3) LDC are typically not found in the hyper-cardioid pattern used indoors for booming dialog, and never found in the "shotgun" super-directional pattern used for open-space situations.
4) LCD typically have "colored" off-axis response. This is used to advantage in a music recording studio. But it is just a disadvantage and an annoyance when trying to record dialog in the field.
 
I tried my AKG C414 B-ULS for an interview once (one of the few LDC that has a hyper setting). While the 414 is a great all-around mic for music, the AT4053 sounded better for an interview.
 
Yeah on the AKG 414! I know what you mean about off-axis coloration, but there have been times where I got GREAT results from it on a boom in OMNI. But, those were VERY controlled interior studio shots where the sounds that the actors generated were exactly what was appropriate for the scene - and the 414 in OMNI delivered it perfectly.

But as a rule - the AT 4053b nails it nearly every time.
 
Thank you all for your replies. I was wondering about that because I only got a LDC so I was wondering if I could use it for actors dialogue and interviews. It's an AKG perception 100 that I purchased 8 years ago. I'm just trying to maximize the material that I already have. I have a cheap but nice preamp that delivers super clean signal for my recorder. What's inherently wrong about off axis coloration? Is it that it gives an unnatural color to room reflections?
 
Marc André Bolduc said:
What's inherently wrong about off axis coloration? Is it that it gives an unnatural color to room reflections?
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The problem with "colored" off-axis response is that it makes it more difficult to control the sound. To separate the desired sound (the dialog) from the ambient noise.
You are fighting against both the unwanted sound AND the coloration of the mic.

But when all is said and done, only YOU can determine whether using an LDC on a boom is practical for YOUR production(s).
 
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Int the old days we used Neuman U87 mics on our fisher booms with no problems but it is recommended that you have a good cradle and a mic with a bass cut to prevent LF bumping.

A 414 or a similar sized mic would be ideal for a boom pole.
 
Yeah, the size of many LDC's is not really an issue at all. Especially the AKG's.

Marc, the off-axis sound you'll get is not going to be a deal-breaker, so don't sweat it. It's just that if you shot the same scene with that mic and also with something like the Oktava MC012 ($300) or the Audio Technica AT 4053 ($550) you are going to like those more - they are going to need less adjustment to get your finished sound you're after.

Just do a bunch of test-shots with your AKG and get to know it - how does it deliver sounds that are right in front of it? How does it deliver sounds that are NOT right in front of it?

It will work. You'll just want something better as your skills get better.

Then save up for an AT4053b.
 
I'll test it thoroughly with my pole. I used it mainly for vocals on music, voice over and a bit of Foley and it worked just fine for that. I have a documentary about the disappearance of aboriginal women coming up so I'll make sure to know if it works. I have a good shock mount but yeah it seems like it would pick up more handling noise than the shotgun I used on one shoot.
 
"it's not a good idea"
Especially in the hands of an idiot (aka, PA).
FWIW, When I had my first 414 (EB), the companion H17A shock mount/windscreen weighed three times the mic.
 
PA= Production Assistant.
The unpaid variety are especially notorious for wrecking/trashing items in all departments.
 
To summarize some of the additional discussion here....
5) LDC tend to be more delicate, more easily damaged if the human-wielded boom hits something (especially the ground).
6) LDC tend to have better low-frequency response which is almost always UN-desirable when capturing dialog on-camera.
Because low-frequency content is almost always noise which you don't want.
And even though you can filter out low-frequency noise in post-production editing, it is not unusual to find
LF noise overwhelming the mic preamp and damaging your audio before you can even filter it.
Which is why some microphones have LF rolloff switches built right into the microphone.
7) LDC tend to be more sensitive to handling noise (because they were designed to be simply mounted on stationary stands).
8) Because of (6), LDC are also more sensitive to wind noise when used outdoors, and require added protection.
9) LDC tend to need bigger and heavier shock-mounting because of (1), (2) and (6)
10) Because of (6), (8), and (9), proper outdoor wind protection (blimp, furry-cover, foam gag, etc.) for LDC
tend to be larger and more expensive for mics not traditionally used for outdoor production.

Of course, none of these are reasons to summarily dismiss LDC for a particular application without doing a proper analysis of the situation.

Back in early days of movie production with sync-sound, they used booms the size of small cranes and microphones the size of your head.
Of course, the practices, crews, locations (typically sound-stages) and schedules were substantially different than what is "normal" today.
And they made much more extensive use of "looping" or "dialog-replacement".
 
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Marc André Bolduc said:
Ok that seems to be a huge hassle especially for outdoor productions. Maybe I should just rent a shotgun with a blimp for that.
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You think that you won't have wind noise inside? Put an LDC on the end of a boom pole and swing it. Actors move. Therefore microphones move. Therefore you have wind noise.

People are telling you to avoid LDCs for dialog. All dialog. But if you want to learn the hard way, by all means knock yourself out.
 
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