Re : Negative,
in order to listen to a wave, we have to be in its path or distinguish some effect it had on something else ... if we are not in it path we can still recover the original signal by applying the appropriate filter... (ie when you listen to an ambulance, the siren start off very sharp then as it goes away it is very fade, it's known as the doppler effect,) the same thing is happening.

As the proper sounds of the bigabang, i don't think it is possible to detect it cuz earth is kindoff in the middle of the milkway galaxy, itself into some other group of galaxy...
i think they've proven that the sounds they can detect with the radio telescope is generated by specific stars/objects in space. it's like in an ee ckt, whatever you do to it they will be noise... call it white/ pink noise; it will be there.

if you were stuck in a empty room 600ft under ground their will still be noises coming .... from you, you breath and your heart bit are strong enough for you to hear them...
hope that helps