General questions about Transient Acoustics and Solid Interaction

Hello fellow Comsol users,

I would very much like to ask a few relatively simple questions regarding transient acoustic models with some regarding transient solid interaction.

In essence my models are looking at how a membrane found in animal ear's behaves to incoming sound pressure, I am only looking to model the membrane not the ear itself. As you can imagine the membranes are very thin (around 1um in thickness and 2000um in diameter). I am doing the models in 3D and am looking at how the membrane deforms in the presence of a sound pressure wave.

I have adapted the Gauss Pulse model to a 3D one. I am modelling the source of the sound as a point Gauss Pulse.

My questions?

1)
Is there a better way to model an incoming sound field? The problem is that I need to place the Gauss Pulse relatively far from the membrane such that the incoming wave has a relatively flat wave front as it comes into contact with the membrane. This however creates relatively large models.

Is there perhaps a plate that I could use as the source of the pulse?

2)
Does anyone know of any other models which I could look at? There are not that many models in Comsol that look at Acoustic-Solid interaction.

3)
Any thoughts or suggestions on how to make the model more efficient.

I have included an image of the model so make things a little clearer.

Thanks very much, I hope there is some discussion to build on the knowledge base on acoustics in Comsol.

Rob