Does the design of the human ear, by which I mean the external part, have some acoustical advantage over just a dish shape? What would it be like to have just a hole on the side of your head, or some other formation? I have never seen a facsimile of the ear shape in any manmade audio devices, do they exist? Basically, why is the ear shaped like it is?
Without getting into a debate on design vs. evolution a large ear can be an efficient reflector to amplify sound over what a plain hole. The shape of the ear probably also helps locate sounds to the front. As for manmade devices how about binaural microphones in a human head shaped housing to capture what a person would actually hear.
Also, part of the reason it’s not just a simple flat dish is that the folds of cartilage give it more rigidity, like corrugated cardboard.
The ear is shaped like it is for two reasons. Firstly it channels sound into the ear much like an ear trumpet, effectively amplifying sound. But that could be done by a simple dish shape.
The folds serve two purposes. The cut down on unwanted echoes much like the irregular shapes on the ceiling and walls in recording studios and auditoria.
They also help us to pinpoint the direction of sound. An experiment was done years ago whereby the subject’s ears were cast in plaster, the pinna covered in latex with a hole left into the ear itself and the cast was attached to the side of the head over the top of the ear but reversed. Upside down and pointing backwards. The subject was then blindfolded and asked to point towards sound being projected form various parts of the room. They located the sounds perfectly with relation to the fake ear, directly opposite to the actual direction of the sound. Using ear casts taken from other people obtained similar results, but nowhere near so accurate. So obviosly the shape of the ear allows us to pinpoint the source of a noise by the tiny delays in sound arrival.
If you just had a hole in your head you would get wind whistling through it, deafening you. When you were inside you would get some echo problems and you would be largely incapable of pinpointing the direction of a noise.
You’re unlikely to see ear shapes in manufactured devices because they tend not to be designed to locate the direction of sound.