Okay...so to give a little more information about this project....
This is a massive (the better part of a mile long) park/green space/multi space performance and meeting venue...some might call it a gathering place
. This is a three year long project which starts this fall with a year and a half of earth moving. The architects, electrical and construction contractors want to finalize the locations and needs for power and sound and light needs for the event productions aspects of this park in the next couple of months so that they can build the electrical and signal distribution infrastructure into the earth moving process.
A colleague of mine and I have been brought in to consult on the sound, lighting, and production power and facilities needs for this project. The first small piece of this project that we have bitten off is figuring out the power requirements, conduit placement and speaker locations to cover a childrens recreation/outdoor classroom area that is about 200 feet long and 80 or 90 feet wide. So, while I am not at the point of recommending a specific faux-rock-speaker; I need to know what general class of speaker I am going to recommend and what power and signal distribution I need to plan to specify, how many and what their placement is going to be. And yes, I know that the answers to those questions can only be given after I determine what speakers are going to be used.
Having said that, the two opposing specs are for:
1) a passive speaker that only needs a speaker cable run to it, but will have a somewhat large amp rack located somewhere...
Or 2) a powered speaker that will require two conduit runs, one for power and one for signal, but that requires a much smaller rack which can be hidden more easily.
From my research thus far, I have not been able to find an off the shelf rock shaped speaker that is a powered unit. So passive may be the only way to go, unless I want to recommend buying powered speakers with custom fabricated enclosures--which may have to be done anyway, as I'm sure the architects won't want to have three dozen rock shaped speakers that all have the same shape.