The entire instrument whether it be the top. the back the sides the thickness of an individual top,is all a big factor in the tone the guitar makes. The sides and back do play a lesser roll in the tone but they definately make a big difference in an instrument. Plywood is stronger but so is the back of an ovation,( hybred fiberglass or whatever the HUEY chopper blades were made from from the 60's--wasn't that Mr Kamans(of ovation fame) original material for the back/side bowl of the ovation? And again those Seagulls I saw had laminated tops. They were still very good playable well built, but they were made on an assembly line process of some sort, and wouldn't ,tone wise, compare to a good handmade instrument