Coupling vs Decoupling


I’m new to this forum and have been doing much reading. I’m aware working with the room and equipment can produce dramatic changes in sound. One topic I’m lost with is coupling vs decoupling. When, where and how to apply each method to produce the best outcome?  

My current system is KEF R900 towers with matching center, R600C and surrounds, R300 and a pair of JL E112 subs flanking a Sony A1E TV.  The room is a bonus room approx 24’ x 14’ with all centered on the 14’ wall. 

Currently the towers are equipped with spiked plinths and subs sit directly on the carpet with their OE feet.  Any feedback about how to best manage acoustic vibrations and when/where to apply coupling or decoupling methods is greatly appreciated. 
jdeickhoff

Showing 4 responses by geoffkait

Generally speaking, a combination of coupling and decoupling achieves the best results. Example, to decouple/isolate a component use mass-on-spring technique. Then use very hard cones or spikes to couple the component to the iso stand AND to couple the stand itself to the floor or rack. This coupling allows residual vibration to exit the iso system pronto. Problem solved!

@geoffkait - the idea of a combination to produce ideal results makes sense and is intriguing. Do you have personal experience with a product you’d recommend?

There is much to choose from for audiophiles these days in terms of isolation products. It all comes down to budget, the weight of the item to be isolated, and location of the item to be isolated, e.g., on the floor or on a rack. You could search for “audio vibration isolation devices” to get an idea of what’s out there.
The trouble with the Gary Koh article is that he didn’t consider mass on spring technology when discussing coupling vs decoupling. He only addressed viscoelastic “isolation” which is not really in the same ballpark. Mass on spring isolation for speakers happens to be a hot topic these days with at least a few Mass on Spring solutions available to audiophiles, including those from your humble scribe. Viscoelastic material is usually found in constrained layer damping solutions, which can be incorporated into mass on spring designs if desired. Kind of depends on what you’re trying to accomplish and how far you want to go.
I sell two types of springs, one type for lightweight and moderate weight components and the other for moderately heavy and very heavy compondnts. See Machina Dynamica’s Page on vibration isolation at,

http://machinadynamica.com/machina25.htm

Geoff Kait
Machina Dynamica