Decoupling made easy
If Aunt Mildred’s fine porcelain is jingling along to the rhythm in its cabinet while you’re enjoying a Motörhead recording, then you have a problem. The same can be said if your record player’s needle happily jumps three grooves ahead when your daughter performs expressionist dance in the listening room. Both are due to a lack of decoupling – i.e. to the unwanted transfer of vibrations.
Decoupling can be achieved with spikes, feet and bases. Spikes are usually included with better loudspeakers, but they can also be purchased afterward. To decouple the loudspeakers, the spike tips must definitely point upward, i.e. away from the floor, otherwise what you have is called coupling, which can also make sense in some cases. Simply stamp your feet in the listening room. If there is any jingling or rattling on your shelves, you must either dismantle and remove the shelf, or decouple the loudspeakers. However, if you have an emotionless concrete floor, coupling can make sense, as it might cause the loudspeakers to emit a clearer, more focused sound.
Basically, hi-fi components do not appreciate being subjected to unnecessary vibrations. Of course, this applies most of all to record players: without exception, these should always be positioned on a suitably decoupled rack or component base, so as to prevent impact noise, low-frequency feedback or the aforementioned “needle jumping”. Tube amplifiers are also sometimes quite sensitive to ambient noise. To use the experts’ term: they are susceptible to microphony. If tubes are shaken, the uncontrolled movement between anode, cathode and grid causes them to generate varying degrees of noise interference. In fact, even transistorized amplifiers and CD players benefit from a properly decoupled “working basis”. A set of four feet can work wonders and is also affordable.