Parametric Design Optimisation, musical instrument (Genetic Algorithm)?

Ok I've got a thought experiment that someone here may be interested in. 

The structure is PVC pipe. The pipes are arranged on a frame which has 5 sides (four sides and a top) in the middle of a room. Each side is covered in PVC pipe. Where the ends are can be struck for a percussive sound. Either end can be struck. Each pipe is one of a fixed number of predetermined lengths, including the length of any elbow joints used. There is no limit to the number of elbow joints used other than the length of overall pipe. 

The ends of one pipe needn't be on the same side. Preferably all pipes end in a 45 degree elbow paired with a 90 degree elbow. 

Each side needs 8 pipe ends on it, and some interesting path of pipes traversing it. 

How do I generate possible solutions to this problem?
How do I optimize this? 

Let me know if that picture is not clear enough.