View Full Version : Is this safe?


Richard Zlamany
September 18th, 2005, 02:56 PM
I was working with a wedding company as a videographer. The boss used his wireless shotgun mic in front of the DJ's speaker for the reception about an inch away. This was his custom. When he tried it that day it was not working right. I didn't get a chance to hear what he meant. He told me to use my wireless lavlier the one I use for the groom to do what his mic wasn't.

I didn't feel it was a good idea so I denied him. The sound that close to the speaker vibrated my entire body. I thought the microphone wouldn't handle it or it could damage my camera. Could either of these two things have happened?

I very cautious with my pd170. Am I too cautious?

By luck the announcments started and we had no time to argue about it so I didn't do what he wanted.

Giroud Francois
September 18th, 2005, 03:24 PM
I shoot a lot of public events with sound system, and for a video camera, the need to be close the loudspeaker is a real pain.
the microphone of the camera can stand for high volume, but they totally fail on bass frequencies. the sound on the tape is usually unworkable.
whant you can do is to wrap the mic into some material (and put something in your ears too) but again , bass are really hard to suppress.
I even got an experience at a fireworks (very very close) that makes the video jump on the LCD screen.
the best is to leave a mp3 recorder with a mic somewhere far from the loudspeaker or even better connected to the mixing out of the DJ.
technically it is hard to destroy a condenser mic, but few inches close to a very powerful loudspeaker for a long time could do the job.

Douglas Spotted Eagle
September 18th, 2005, 05:16 PM
You're being way too cautious, IMO. You wanna know when to be scared for your camera? Try being on board the USS Stennis when the LADAR/RADAR system sweeps. It vibrates the camera so bad, and screws up the image so bad, you wonder what's happening to your body. The camera is fine, so long as it's not in the sweep. It's pretty hard to damage a condenser mic with just volume. Morton Thiokol uses AT condenser and Shure dynamics on test rocket motors, and while I've never stood next to one firing, you can probably feel safe in assuming they're much louder than any loudspeaker you can stand near.

Richard Zlamany
September 19th, 2005, 01:23 AM
Thanks, I'll try to loosen up more.

Greg Bellotte
September 22nd, 2005, 10:15 PM
It's pretty hard to damage a condenser mic with just volume.

Tell that to Sennheiser, and the 10 MKH-416's I've damaged at NHRA drag racing events in the last year... :-) glad I don't pay for them...

Douglas Spotted Eagle
September 22nd, 2005, 10:18 PM
Welcome, Greg! You shooting over at Rocky Mountain Raceway?

SPL isn't quite the same as vibration messing up a cam...but I'm sure curious about how you'd be damaging the MHK's. Overpressure more than likely? Sticking those mics inside the dragster's exhaust probably isn't all that good for them. :-)

Stephanie Wilson
September 22nd, 2005, 10:46 PM
You're being way too cautious, IMO. You wanna know when to be scared for your camera? Try being on board the USS Stennis when the LADAR/RADAR system sweeps. It vibrates the camera so bad, and screws up the image so bad, you wonder what's happening to your body. The camera is fine, so long as it's not in the sweep. It's pretty hard to damage a condenser mic with just volume. Morton Thiokol uses AT condenser and Shure dynamics on test rocket motors, and while I've never stood next to one firing, you can probably feel safe in assuming they're much louder than any loudspeaker you can stand near.

Douglas,

What causing your camera image to distort during an aircraft carrier radar sweep is the RADAR. BTW you can protect your camera to some degree by wrapping it in double weight tin foil or similiar product. Does a fairly good job at deflecting the radar.

As for the mic question, I've put a very expensive lav mic two inches away from a speaker, but I wouldn't try it with my own lesser quality Sennheiser 100G2 or Sony ECM-44B. IMHO, it's better to be safe than sorry when protecting your own investment.

Douglas Spotted Eagle
September 22nd, 2005, 11:29 PM
Douglas,

What causing your camera image to distort during an aircraft carrier radar sweep is the RADAR. BTW you can protect your camera to some degree by wrapping it in double weight tin foil or similiar product. Does a fairly good job at deflecting the radar.
.

Yeas, I'm well aware of this, and also aware of other options. I was on the Stennis training the military, not getting footage for a shot. So, I had the privilege of being there for several days, and experimented with a number of things.

Stephanie Wilson
September 22nd, 2005, 11:44 PM
Yeas, I'm well aware of this, and also aware of other options. I was on the Stennis training the military, not getting footage for a shot. So, I had the privilege of being there for several days, and experimented with a number of things.

Dear Douglas,

I may be shooting another RIMPAC war game exercise off numerous air craft carriers again. Would you mind sharing your "other options" and "other things" with us all?

Steph

Greg Bellotte
September 23rd, 2005, 03:55 PM
@Douglas
Thanks! Sorry, never been to RMR. Was in Reading, PA last week and will be at Route 66 raceway next weekend.

Yes, the damage to the 416's is overpressure. I've taken readings of 150 db/spl near some of the mics, but that is as far as my meter goes. Actually used a seismigraph once, 2.2 ricters! I've also lost a few SM-58's and EV635a. I'm hell on equipment... :-)

Glenn Chan
September 23rd, 2005, 05:43 PM
I've also lost a few SM-58's and EV635a.
I'm curious: how did you manage to do that? People keep telling me the SM58 can be used as a hammer.

Douglas Spotted Eagle
September 23rd, 2005, 05:59 PM
I'm curious: how did you manage to do that? People keep telling me the SM58 can be used as a hammer.

It can be used as a hammer, but overpressure that forces the element to move past it's boundary too quickly can kill the mic That sort of overpressure will kill just about anything, including your ears. (OK, *especially* your ears)

Marco Leavitt
September 23rd, 2005, 07:03 PM
Greetings Greg. I went to the U. in the '90s. Always glad to see another Utahhhhn in here.

Ty Ford
September 24th, 2005, 05:51 AM
I'm curious: how did you manage to do that? People keep telling me the SM58 can be used as a hammer.


I've seen this more than once recently. As far as I know, the "hammer" mic is really the EV635A. It can withstand a LOT more than any SM58.

Ty Ford

Greg Bellotte
September 24th, 2005, 06:46 AM
what can i say, next to the space shuttle I get to mic the loudest thing on earth. sound pressure levels exceed 150db/spl where I put microphones, eventually they fail. those poor little element diaphrams can only take so much abuse before they tear or get stuck outside their intended travel. the people that pay the bills don't want to buy more expensive mics (that wouldn't fail) because of the history of failures. go figure, hire an expert...ignore his advice. why is that?? :-)

@ty
yes, the 635 is the "hammer". named such because the EV demostration years ago would have the presenter use the 635 he was speaking into to actually drive a nail through a board. "That's one tough microphone..."

@marco
only live in utah. well, actually just a house there-i'm never home. still consider myself a Floridian, just now without tan...

Douglas Spotted Eagle
September 24th, 2005, 08:59 AM
In terms of demonstrations, EV started that, but it wasn't long before Shure started doing the same thing with SM-58's and 57's (same mic, different cartridge) Terry Richardson in SLC still does this once in a while. Since you're in Utah, Greg, you might remember the old display that Kevin had at Performance Audio where someone slipped with a 58 and the nail when through the ball/grille. Was a cute little sculpture.

We're in Utah too, about 45 mins west/south of SLC.