Over the span of a few years we were able to hear many different systems both here in our own building during concerts and at other venues in the area. Coverage, gain before feedback, and vocal intelligibility were our biggest concerns. Once we heard the ISP line array, we knew we had found our solution. We are very happy with the way the HDL 4210 speaker system has been able to handle whatever we have thrown at it, including the capability to really rock the house when we need to. The system has amazed everyone that has had the chance to hear it.