Yes, but you can't copyright the technical structure - so the acoustically designed internal structure can be copied unless it's protected by IPR other than copyright (patent, industrial design rights, whatever). The external appearance, AIUI, is chosen primarily on artistic merit and so would be under copyright. Facets that are technical, how panels are adhered, how drainage works, they could be copied.

Using this as an analogy for the API would mean anything that was part of the technical implementation could be copied but inconsequential or artistic parts couldn't. This has been interpreted to mean that the actual code is "creative", so you'd have the framework of the code but not the non-essential parts that could be different and still allow the API to work.