Original thoughts on how the sound might be described.   Note that the sample 
sound is not what will be in the show, just a way of making real the description 
below:

Deep bass rumblings seem to rise up, almost subliminally, surrounding and 
immersing the audience before they are fully aware that it is happening.  Use of 
deep sound to create the affect of approaching dinosaurs, or far away rumbling 
armies.  Sounds that are barely audible, giving a sense of life and energy to 
the visible objects.  A vibration that suggests much more and gives a sense of 
constrained power.   Bass sounds are dense and full of detail, like deep 
distorted radio signals forming a 'sea' of sound seeds and suggestions from 
which specific elements can briefly rise and take shape before sinking again 
into the mix.   The deep, subliminal, rumblings must convey a feeling of being 
in the middle of a large world - so that the audience feel that they have been 
beamed down into an unknown landscape (or the landscape has materialised around 
them) rather than the sounds simply eminating from the structures in the show. 
However, within this bass-sea, the 'breathing' of the structures must be 
apparent and obviously come from them.   The sounds begin to pulse in an barely 
discernible way.   Their sounds are similar but distinct.  There is a feeling 
that energy is being shared or exchanged. They pulse independently (from within 
the sea of bass noise) but still seem to affect or reinforce each other.   No 
real 'music' at this stage but distorted suggestions and snippets of 'music-
like' sounds.   Possibly sounding as though someone had collected all the sounds 
and music that had occurred in that place over the years, put them all into a 
big pot and boiled them together for a very long time, leaving a dark ,bubbling, 
steaming brew, with only the faintest traces of it's original constituents.   

The atmosphere is relaxed, sleepy (hibernation) but with an increasing awakening 
- early morning, dawn, the day ahead yet to begin.   But things are cooking, 
digesting, incubating - perhaps the hills have not been sleeping but have been 
busy preparing for the next stage (lion digesting an antelope before the next 
hunt, pigeon warming eggs before dawn permits more food gathering).   Faint 
whispers, rustlings, (clicks) become apparent, appearing in random places, very 
quiet, like the faint echoes of a long ago party (or dawn fairies rushing about 
their business!!!). These are very distinct from the 'bass sea', being higher in 
pitch, light and ephemeral.   Out of the bass noise sea rise discernable bass 
voices coming from the hills - like deep distorted whale song rising above the 
surface. Initially, just occasional groans or contented hums. These are the 
voices of the hills. The image is of a dark undulating sea in which giant 
swimming creatures (whales, serpents, loch ness monsters) occasionally break the 
surface as they swim onwards on their endless journey, emitting gentle giant 
cries as they do so. Warm but tinged with sadness in that giant melancholy kind 
of way.   These bass-song phrases form a very slow call-and-response between the 
hills, initially using just one or two simple constructions that they seem to 
echo back and forth but gradually building in scope. Bit by bit a simple 
vocabulary emerges. The feeling is of the hills reassuring each other, keeping 
simple contact, passing the time of day, swapping/checking simple information.