These are compression waves and unlike light waves, they must have a medium in which to travel. They can pass from one medium to another enroute to your auricle canal (your ear). Each medium will alter the wave energy properties so that the original wave is very much different from the wave that you eventually perceive. This drum is an excellent example of that.
First and foremost, at this frequency, the sound wave's wavelength is very small. Because compression waves (or longitudinal waves) must have something to discern their presence in order to be "heard", the heads will dictate the sound quite a bit. Not entirely, but it has a major impact. The smooth surface of the inner ply of wood will reflect a lot of the waves, but will only partially vary the perceived tone. Because the wood still maintains some of the roughness, some of the waves will be absorbed which reduces the available energy. As far as the shape ... it's really not so much of a factor at this proportion. It forces the shell to play a larger role, but as stated, that is only minimal. This is where wood selection is involved, but that is another discussion.
The major major major variable to consider here is the resonant head size in proportion to the batter head size.
The batter head pushes the air which acts as the medium for the energy to travel. When that wave energy strikes the much smaller reso head, the tension (or change in the medium) affects the frequency, amplitude, velocity, speed, and wavelength. That changes pretty much all of the wave properties of the initial wave produced. THAT altered wave is what travels through the air (the next medium) to your ear. When THAT wave strikes your tympanum, it is what you perceive as the sound of that drum.
I love the conical drum idea. I've searched for a sweet set for several years, to no avail. If I could find a company that would make them in a much darker wood (think African Mahogany), with rounded edges for calf, I would wet myself. The tone would be absolutely breathtaking.