Best way to record gunshots + dialogue?

[Izen Ears]

  I'm doing a scene with these M-16 type guns, automatic, full charges and REALLY loud.  They insisted on full charges because they want to make sure to get some good flaring out of the barrels (they do look good). 

  I'm using the CMIT with a UM400, dial set all the way down (around 8 o-clock) and the shots sound really awesome and not distorted set like this.  But, when the shooting's done they have a long dialogue and cranking up the CMIT gives of course a massive hiss.  The three actors have lavs but they're full of fabric noise in their non-cotton combat uniforms (Sankens with the rubber boot and topstick). 

  I thought about putting another boom in the room on a stand just for the shots and having the CMIT at a normal dialogue value, but I worried it might hurt the UM400 and/or my mixer and deck?  The actors' wires totally max out on the shots and then the dialogue sounds fine (other than the fabric noise).  Is it safe to assume there's no damage to the UM400, the Cooper 306, and the PD6 even though the shots are ear-splittingly loud?  (My boom and everyone in the room [but the actors!] are wearing earplugs.)

  We are covering the scene in tights without shots fired so I can get good boom sound on the lines, but I want to get the best sound possible for the wide...

  Dan

[ProSound]

I would never use a delicate and expensive microphone like the CMIT near loud gunfire as the SPL can damage the microphone. I would be using the "Stand in" the Octavia as many other mixer would or make a MKH 416.

[Guest afewmoreyears]

I would never use a delicate and expensive microphone like the CMIT near loud gunfire as the SPL can damage the microphone. I would be using the "Stand in" the Octavia as many other mixer would or make a MKH 416.

Whit,

Could you please re write this.....  can't understand your point here.... the last part....

Thanks

[Jeff Wexler]

Any condenser microphone can be damaged by high sound pressure levels (like explosions and gunfire). This damage can occur even if the microphone is not plugged in and just sitting on the set. What Whitney is saying is that it is preferable to put in jeopardy a $200. mic over a $1700. mic. I have done many scenes with the Octava (and similar low cost condenser microphones) where there is gunfire and dialog. Sure, the dialog may suffer a bit and I may have to do a lot of really screwy on the fly gain changes (trimming the microphone preamp is not so easy to do if its hooked up to transmitter, but I have never done that). The larger problem, as I see it, is that if it is crucial dialog, nobody is going to be hearing it properly because everyone, including the actors, will be wearing ear plugs. The ear plugs are a necessity and many actors, the good ones, will request that the dialog be done AFTER the shooting, after a cut, so they can pull their ear plugs out and hear what they're doing.

The other thing about using an inferior mic for the dialog in these sorts of situations is that the "dialog" that has to be recorded is often not crucial low level stuff, but rather action noises, yelling, etc. This is obviously not always the case but if it is quiet crucial dialog, most actors and directors will want to shoot this in coverage without worrying about firing the guns.

-  Jeff Wexler

[berniebeaudry]

Any condenser microphone can be damaged by high sound pressure levels (like explosions and gunfire). This damage can occur even if the microphone is not plugged in and just sitting on the set. What Whitney is saying is that it is preferable to put in jeopardy a $200. mic over a $1700. mic. I have done many scenes with the Octava (and similar low cost condenser microphones) where there is gunfire and dialog. Sure, the dialog may suffer a bit and I may have to do a lot of really screwy on the fly gain changes (trimming the microphone preamp is not so easy to do if its hooked up to transmitter, but I have never done that). The larger problem, as I see it, is that if it is crucial dialog, nobody is going to be hearing it properly because everyone, including the actors, will be wearing ear plugs. The ear plugs are a necessity and many actors, the good ones, will request that the dialog be done AFTER the shooting, after a cut, so they can pull their ear plugs out and hear what they're doing.

The other thing about using an inferior mic for the dialog in these sorts of situations is that the "dialog" that has to be recorded is often not crucial low level stuff, but rather action noises, yelling, etc. This is obviously not always the case but if it is quiet crucial dialog, most actors and directors will want to shoot this in coverage without worrying about firing the guns.

-  Jeff Wexler

To tag on to Jeff's excellant advice.  Consider using a dynamic mic just for the gunshots. They can withstand higher sound pressure levels without overloading than condensers.  You're really limiting yourself for level control by using a wireless boom.  Might consider using a wired boom instead.

Bernie

[Rob Lewis]

I would agree that using a wireless boom is not a good idea as the gain changes would be too hard.  Second, I the dialogue is important than you must make the producer understand that it is not usable during the gunshots and that all dialogue will have to take place after the shots.  I would personally get the CMIT5 as far away from that set as possible!

How many audio tracks are available and what if any camera are you shooting on?  If you are shooting on a camera that has dedicated camera mic to ch 3&4, I would mount a cheaper condenser or dynamic mic for the gunshot audio and use a hardwired boom or the lavs to pick up the dialogue.  Something like a 416 or Me66 if you are gonna boom the dialogue.  Smaller loss if the capsule blows!

If your using the lavs, I would turn down the transmitter gain some in order to minimize the excessive gunshot level to the transmitter and when the speaking occurs, and I would makeup that gain with the mixer.  This of course is not the ideal gain structure but you are recording in an extreme situation.  You may want to consider using a less sensitive and expensive lav as well.  Countryman EMW's work good for this situation.  They are not a sensitive, tough, cheap to replace and sound pretty good as well.

[Arnold F.]

In all the time I cut sound effects we never, ever used the gunshots recorded on set.  I would worry only about the dialogue.

best,

A.

[Guest afewmoreyears]

I agree with Arnold....

  Concentrate on recording the dialog.... the gunshots are almost ALWAYS laid in later. The gunshots used are usually layers deep of recorded shots to come up with the sound we all know as gunshots....

  Let the post guys and gals work their magic....

[Izen Ears]

  Well I took your advice all of you nice mixers who chimed in.  Instead of the CMIT or MK41 I subbed the AT 4051 and basically let it max out at the shots and then got the dialog after the shots.  I left the Sanken lavs on the talent and they didn't seem to be harmed, but the AT 4053 seems now to have a strange rumble.

  We're using a couple Arri 235 cameras so all sound is on the PD6, otherwise yeah a dynamic mic would have been great! 

  Then we had a couple squibs on products to effect shotgun blasts in a store - THOSE were loud!  For those I used a dynamic mic cranked down and it was fine. 

  I have to say that the recorded gunshots, when the transmitters and inputs were turned way down, sound great!  Very unlike the typical canned sound of lots of movie shots.  I hope the post guys use them because they do not sound canned at all.  And what reverb!  Super cool.

  So hey, if either the Sanken lavs or Schoeps were to have sustained some damage, what would that sound like?  Does a rumble on the AT 4053 sound like damage from a loud-ass noise?  Thanks a million for the advice, it gave me the confidence to tell the director that taking the whole scene from top to bottom with shots was going to sacrifice sound in a big way.

  Dan

I would agree that using a wireless boom is not a good idea as the gain changes would be too hard.  Second, I the dialogue is important than you must make the producer understand that it is not usable during the gunshots and that all dialogue will have to take place after the shots.  I would personally get the CMIT5 as far away from that set as possible!

How many audio tracks are available and what if any camera are you shooting on?  If you are shooting on a camera that has dedicated camera mic to ch 3&4, I would mount a cheaper condenser or dynamic mic for the gunshot audio and use a hardwired boom or the lavs to pick up the dialogue.  Something like a 416 or Me66 if you are gonna boom the dialogue.  Smaller loss if the capsule blows!

If your using the lavs, I would turn down the transmitter gain some in order to minimize the excessive gunshot level to the transmitter and when the speaking occurs, and I would makeup that gain with the mixer.  This of course is not the ideal gain structure but you are recording in an extreme situation.  You may want to consider using a less sensitive and expensive lav as well.  Countryman EMW's work good for this situation.  They are not a sensitive, tough, cheap to replace and sound pretty good as well.