This is a quick demonstration video showing how in-phase signals add and out-of-phase signals cancel each other. I used identical copies of the same source audio for the simplest demonstration.
If you’ve been reading my blog for a while you probably know that most of my work is small scale and happens in very safe, controlled environments. No elaborate sets or complex rigging. I recently did a shoot in a restaurant which required mic stands extended over a group of about 12 people along with a few tripods, a light on a stand and a backdrop on a support system with two stands. $25 and some pre-planning helped me keep my risk a lot lower for the shoot.
All I did was add four sandbags to my existing gear to make it a lot harder for someone to tip over any of my stands. This turned out to be a good thing when one of the talent caught the edge of a stand with his foot. It moved slightly but did not fall and he was fine. No lawsuits and no disruption to the shoot.
I chose PBL Saddlebag style sandbags with bright yellow stripes. Not only do they hold down the stands, they also make them more visible and less likely to be tripped on. I bought a 60 lb. bag of sand at the local hardware store for about $5 to fill them with and added some plastics bags as a 3rd layer of defense against leaking sand (there are two layers of zippers in the Saddlebags).
Be smart and take care of the easy, inexpensive things that can keep your shoot on track and keep you out of the courtroom.
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