Todd Whitford of Gabriel Sound, located in Pompton Lakes, New Jersey, needed to hang two QSC MD-FP122/64r powered speakers in a gymnasium. The gymnasium is part of the St. Francis Church, in Metuchen, New Jersey. As can be seen in the photographs, a basketball hoop and backboard, with its support structure, takes up quite a bit of space in front of the stage. Todd’s first choice was to do a center hang of two, depending on ceiling height and backboard height. When he talked it over with Mike Akrep, engineer for Polar Focus Audio Rigging, it became clear that his second choice, a left right hang, would be better, as it would not have to be built around the backboard structure already there.

After that was determined, Todd had to decide how to position the speakers in the left right configuration. He decided that he wanted to hang them horizontally, so they would be protected from flying basketballs, and conveniently the QSC MD full-range models feature a rotatable high-frequency horn which enables them to be used either vertically or horizontally. A yoke for attaching to the speakers was available from Polar Focus. Components from the Polar Focus XY Grid System, along with two spreaders, were attached to the yokes. A feature of any XY Grid custom assembly system is adjustable left and right pan angling. So, once Todd had the two speakers attached to the ceiling, he could adjust their angles correctly.

But attaching to the ceiling was a little bit tricky, as the ceiling is slanted. Pairs of purlins left and right were chosen. Holes were drilled in the correct locations in the purlins to accommodate rigging chain sling kits. As the purlins are at different heights in the slanted ceiling, attachment between the eyebolts on the spreaders and the shackles on the chain slings had to be of different lengths. On each of the spreaders, the distance between the chain sling shackle and the spreader eyebolt on the end going to the lower, or bottom, purlin, was a shorter distance than at the other end. Here the eyebolt and the sling shackle could simply join up. However, on the other, or top, purlin, attachment between the eyebolt and sling shackle needed something added. That something was a 3/8 X 6 inch Chicago Hardware turnbuckle, providing that extra bit of adjustability necessary in making these speakers hang evenly. With this cure for uneven purlins, Todd got just the right slant on the job.

www.polarfocus.com
www.speakerrecone.com (Gabriel Sound website)