Published at Wednesday, July 31st 2019, 07:41:33 AM. Speaker Stands. By Cort Friedrich.
The theory is that the mass and spring characteristics are chosen so that the resonant frequency of the combination is well below that of any frequency they’re likely to be asked to isolate. For example, if the lowest note a speaker can reproduce is 30Hz, then the resonant frequency of the supporting platform needs to be well below that — perhaps just a few Hertz or less.
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.
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.
You can make a speaker move less in many different ways, and one of those is by adding more mass to the speaker and the stand; making it harder for the speaker to move. That’s why you’ll find a sand compartment in most stands.