Can I suspend / hang speakers?

Swampwalker, be carefull of intuition and "common sense", they are what people use to explain that heavier objects fall faster than light ones.
The movement caused by the counter movement of the speakers can be calculated to be virtually, if not literally, nil.

inpenin- I agree with your comment on intuition. Point made. However, I do not believe that allowing a speaker to move freely in space (even a small amount) is beneficial to good sound. I must admit I will NOT hang my 90 lb Merlins from the ceiling when they arrive to experiment.

Ok, has anyone done the math? I'm no physicist, but can't you figure out the force caused by the displacement of air for a single note, the force caused by the movement of the voice coil, and, based on the weight of the speaker, figure out how much reverse displacement would be caused? Wouldn't that give you a damping factor? Granted, its probably totally ballpark, but I'm guessing to would not be "virtually ... nil."

I'm curious, because of my experience with my old ProAc RS2s. They sounded awful until I mounted them on the recommended Target sounds, and then they sounded awesome.

The speaker cabinet will indeed move in response to the cone and this movement will be quite small by daily human standards. However, this small movement IS in my view enough to smear the sound. I cite the same reasons as others on this thread for rigidly mounting speakers to stands.

Given that woofer cones are generally made to be as light as possible and that the reverse is true for speaker boxes, the reaction movements of the box are indeed very slight, but not in my view insignificant.

Bottom line is that this system is for "dad" who is not likely an audiophile, else he'd be setting it up himself. With some folks esthetics, convenience, whatever far outweigh imaging, purity of tonal balance and the rest of our arcana.

My advice is to make sure that the system is safe - the hooks have adequate safety margins, the cables don't get tangled with the raising/lowering, etc. - and then let your dad enjoy it.