By Wilde Becker. Speaker Stands. At Wednesday, July 24th 2019, 02:55:42 AM.
Fortunately, we don’t need to balance the speaker on actual springs, as a suitably dense piece of acoustic foam can act as both spring and damper. The speaker cabinet provides mass — so sitting a speaker cabinet directly onto a piece of foam, such as an Auralex MoPad, will bring about an improvement in the amount of vibrational energy getting through to the desk. However, foam isn’t particularly rigid, so the cabinet may still tend to move back and forth slightly as the speaker cones move, especially if the speaker cabinet isn’t particularly heavy.
Many stands come with a compartment dedicated to sand and similarly heavy and well-damped materials. And there’s method in the madness. You see, the speaker plays music by moving its drive unit in and out to create sound pressure: when the drive unit pushes outwards, it creates sound pressure, but when it moves inwards it pushes the entire speaker backwards.
Furthermore, in accordance with Newton’s third law of motion (each action has an equal and opposite reaction), whenever the speaker cone moves in one direction it will try to push the speaker cabinet the other way.