Published at Saturday, December 28th 2019, 02:57:45 AM. Speaker Stands. By Ekerd Werner.
You could just plonk your speaker onto the top of your chosen stand, of course, but it’s best to have the speaker fixed to the stand in some way, because otherwise it can slide around. One popular and effective method is to place blobs of Blu–Tack under each corner; this acts as both a removable adhesive and as a damping medium. Another alternative is to use high–friction rubber matting, of the type sold for workshops and kitchens.
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.
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.