( very ) loud stage sound vibrates video camera

wilvan wrote on 3/13/2013, 12:09 PM

Maybe some of you have some experience and can give some advice .

Am video recording a danceshool show each year ( hiphop - modern ) .
Have been using the sony HVR-V1E HDV camera mounted on a libec tripod ( T98carbon tripod and fluid head ) .

The music on which they are dancing is always very loud with deep base .
When the base is very deep , the recorded video gets blury on the rythm of the deep base sound .

Some people with similar issues advice to de-activate the image stabilizer on the camera ( since mounted on tripod ) , some people advice to throw sand bags against the tripod legs to dampen ( rather .... ) .

I managed last year to convince the sound operators to slightly lower the decibels but still the base sometimes goes through the chest ..........

Anybody having some ood advice here ( spot to shoot can not be changed ) , very welcome since within a few weeks it is dancing shooting time again .

Thanks

Back to post

Comments

Laurence wrote on 5/18/2013, 8:25 AM

That's not what I find. What I find is that when the subwoofer is out from a wall, low frequencies go back to the wall, then bounce back creating cancellation patterns which have the effect of making loud and soft sub bass areas throughout the room. But what do I know, I've only been doing sound professionally since 1988. The common answer that people give is that subwoofer placement doesn't matter because bass is undirectional. Yes low frequencies are non-directional, but they are also huge. Put a subwoofer out from a wall a little and you will have all sorts of phase cancellations throughout the room. By the way, I'm heading off to Tampa this afternoon with my own subwoofer packed into the back of my SUV. I will use this principle tonight. If I didn't I would have some people not really feeling the bass, and others complaining because it was too loud.

Laurence wrote on 5/18/2013, 8:40 AM

I found this guide to subwoofer placement:

http://www.audioholics.com/tweaks/speaker-setup-guidelines/subwoofer-placement-guidelines

Here is a picture showing a typical placement. Notice the subwoofer in the left corner and the bass trap in the right:

Here are more random subwoofer placement drawings:

Often you don't want to stick it directly in a corner because that will concentrate the bass into the opposing corner, so you will offset it slightly like this:

Laurence wrote on 5/18/2013, 8:43 AM

Anyway, my point is that even with the best subwoofer placement, there are going to be hot and soft bass points throughout the room. Your camera is likely in a resonant bass spot now. Move around the room with the bass pumping and listen and feel for the places where the bass isn't quite so strong. If you can, move your tripod to one of these and you should have much less of a problem.

musicvid10 wrote on 5/18/2013, 8:50 AM

A typical low subwoofer frequency of 40Hz has a wavelength of 28.25 feet. So in Laurence's example (subwoofer close to a wall), phase reinforcement is a certainty, and phase cancellation a virtual impossibility. Yes, the reflected wave will make it sound louder. Ideal subwoofer placement is a single cabinet placed in the center of the acoustic space (remember "coffee table" subwoofers?).

farss wrote on 5/18/2013, 8:58 AM

Quite regardless somehow I just don't see this going down too well with the average sound guy:
[I]Can I have a feed from your desk and can you move your 2 tons of subs so they don't shake my camera...please[/I]

I know what I'd being, fixing MY problem myself and being as nice as possible to the sound guy.

Bob.

stillruns wrote on 4/9/2017, 11:29 AM

I tried a number of things to prevent camera bounce. I put the tripod legs on anti-vibration pads with folded up towels on top of the pads. And used a heavy weight to pull the tripod toward the floor. This didn't work out. What did work very nicely was to put the tripod on cotton balls stuffed into ziplock baggies. I assume small pillows would work about the same. If you're using a real cheap (feather light) tripod I'd recommend using a pound or two of weight added to the tripod. If anyone has luck with this or with other variations, let me know.