By Wilde Becker. Speaker Stands. At Tuesday, July 30th 2019, 19:05:28 PM.
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 may have noticed that some speaker stands are fitted with spikes on the base, which help to make a rigid and stable contact with the floor. As long as the stands are both robust and stable, this strategy works well on solid floors, but you may find that it causes problems on wooden floors, due to vibrations from the speaker cabinet being transferred to the floor via the rigid stand and spikes. The floor will then act as the king of soundboards!
It’s physics: for every action, there’s an equal and opposite reaction.
Their smaller stands are made from a type of plastic and their larger ones from cast metal. All are perfectly valid approaches. Note that some speakers, such as certain Genelec models and Event’s Opals, already come with resilient isolating platforms or feet and so may not need additional treatment.
The heavier the stand, the less it will move, and with many hi–fi and pro–audio speaker stands (including many of the models made by Atacama, for example), it’s possible to fill the hollow support column with a heavy material to add mass and to damp resonances. This could be sand, shot or any other heavy but well–damped material.
One way to improve the situation is to add mass by means of a platform fixed to the top surface of the foam. Primacoustic do this in their Recoil Stabilizer by using a very thick steel slab with rubber matting on top, while Auralex and other companies use MDF topped with dense rubber on their more up–market platforms. IsoAcoustics take yet a different approach, by using a frame made from rigid components joined by resilient isolators.