How much does sound weigh?

Answer 1

Sound in air is simply a compression of air at the frequency of the sound. The sound itself does not weigh anything, but the medium it is travelling in will have its own weight per unit volume.

Answer 2

Sound does not have a weight because it is a form of energy that travels through matter as vibrations. The weight of an object is determined by the force of gravity acting upon it, but sound itself does not have mass or weight.