And about the sonic gunazullathingie.
Sonic propagation is equal to vibration in a medium. Vibration is created thru force transmission at an interface when the force is not constant and is not linear upto 2nd degree. If u push something very slowly and if you increase the force evenly along time there wont be vibration. Vibration is the way a system tries to settle/come to a stop when it has been introduced instant kinetic energy, like hitting something with a club, shooting with a bullet. Vibrating some object at random is just vandalizing it, there is no point, u can punch holes to it with bullets instead. The one and only point of using sonic weaponry/induced vibration to an object is making use of its harmonics that is the all famous "natural frequency" to bring it into the allmighty "Resonation" condition.
To make thing a little more easy to grasp, i need to tell what these shit are. Take a 2 lbs steel ball, tie it to the end of a 3 ft rope, tie the other end of the rope to the ceiling. Now pull the ball to one side a few steps and release it. You have vibration here. The time it takes for the ball to leave your hand and come back to the same point and stop there for a split second is called Period (T) and you can calculate it with this.

If i did not get it wrong when you put our values, the period is 1.931 second. As you see the result it completely independent from the mass you put. Just the ropes lenght and gravity. Period is what it takes the ball to make a trip and back, frequency is the number of back and forth trips it makes in a total of 1 second.
f = 1/1.931 sec = 0.517 (1/sec) = 0.517 Hertz
So this is vibration, and in ideal conditions, there is no friction and such, so the pendulum goes back and fort forever at that specific frequency. (say in space, with near 0 friction very thin frame structure etc) But in real world there is friction, and there is dampening. As long as we work in real world there is a dampening action always. That pendulum will stop moving at some point, thru friction with air, or internal friction of the rope or the nail that fastens the system to the ceiling.
Thus we have natural dampening at normal systems and thus when i hit a tank with a hammer the entire body vibrates and then comes to a stop. The displacement i make at one end, travels thru the body and exits from the other sides. As the pendulum when i hit the tank at the same point again and again (not necesarily with the same force), the sound frequency of the sound will be always the same, if i hit harder, the sound will be louder and it will take more time for the tank to stop vibrating. This special FREQUENCY, that is entirely dependent of the geometry and material structure of the object in question is called NATURAL FREQUENCY. It is a specific attribute of every object, it doesnt change (unless geometry and density changes thru temp change or something)
Now we know nearly everything, lastly we need to know what displacement is. Displacement is the amount of distance the ball in the pendulum travels from resting point when it stops momentarily at one side. When hitting a tank, the displacement is much much lower, thus the frequency is higher (our ears can perceive a specific frequency range, the movement the pendulum does is not audible for us, but it maybe for other beasts like elephants) Free mode vibration is a fairly complex subject (which i failed once in undergrad

) but what we are gonna use is one of the most basic concepts, RESONANCE. When you hit the the ball of the pendulum, it begins to swing with a its natural frequency. If you can keep hitting it just with the same frequency as it is ossilating, the displacements you get at each excitation get on top of each other, and when given enough time you keep the exciting the system at its natural frequencty the "displacement" will lead to infinity (this doesnt happen mostly thru physical reasons, such as the natural frequency changing when geometry changes dramatically).
This means you can rip some structure apart fairly easy if u apply the vibration with the right frequency to it.
This is all that is behind the sonic weaponry actually, because normally sound waves really dont carry much energy and they are far far far from being feasable as weapons of destruction, but just this resonance property makes it feasable.
And how do you induce vibration from afar thru void? Actually as i said even when there is a thick athmosphere in between it wouldnt work quite right with capital ships and such. For them you need to exploit other stuff like other remote force transmission methods like magnetism, or gravity. If there is a high charged particle stream in a ship, you can excite it from a far thru magnetic fields. Or you can use the old gravitons, since they are purely theoretical particles(?) you can ASSUME anything about them in a game

Feel free to do that.
Wow, it has been a long post, sorry about the bad formatting, i am completely new to this forum business.