If you search back, you will find about 101 posts on this topic and many answers to wade through that both support and refute the benefits of decoupling. Folks around here have been decoupling speakers with things like hockey pucks well before the more recent craze of decoupling products became available. To your question about a "theoretical explanation" I have linked videos from manufacturers Townshend and Credo, as well as an article on IsoAcoustics Frequency Response Testing at the National Research Council of Canada, and a thread posted about springs on the dreaded Audio Science Review. I hope this helps - draw your own conclusions, and good luck convincing your "very knowledgable audiophile friend"!
To couple, or not to couple, that is the question
There seems to be a fundamental difference of opinion between those who would couple their speakers to the floor (e.g., with spikes), and those who would decouple them (e.g., with springs). I’ve gone both ways, but have found that I prefer the latter; I’ve currently got Sorbothane feet attached to my tower speakers, so that they wobble or "float"—much like the Townshend Platforms videos show for that similar, but more expensive, approach. My ears are the final arbiters of my listening experience, so they rule my choices. But my mind likes to have a theoretical explanation to account for my subjective preferences.
That’s where the question comes in. A very knowledgable audiophile friend insists that what I prefer is precisely the opposite of what is best: that ideally, the speaker enclosure should be as rigid and immovable as possible so that the moving cones of the drivers can both most efficiently and most accurately create a sound front free of the inevitable colorations that would come from fighting against a moving cabinet. He says that transients will be muddied by the motion of the cabinet set up by the motion of the speaker cones. And this makes perfect sense to me in terms of my physical intuitions. It’s perhaps analogous to the desirability of having a rigid frame in a high-performance vehicle, which allows the engineers to design the suspension without having to worry too much about the complex interactions with a flexing chassis.
Am I just deluded, then, in preferring a non-rigid interface between speaker and floor? Or does it depend on the kind of floor? (I get that most advice seems to favor decoupling from a suspended wood floor, and coupling to a slab; my floor is hardwood, but not exactly "suspended" as the underflooring structure is very rigid.) Or are there trade offs here, as there usually are in such options: do I gain something (but what, and how?) even as I lose something else (i.e., clean transients, especially in bass tones)?
The ears will win this contest, but I like to have my mind on board if possible. So thanks for any input you may have on this question.
Showing 6 responses by mitch2
I believe you have a SA stand as I do also. As an inexpensive solution, I use velcro looped around heavy power cords and then around the rack above to help relieve the weight hanging off of the component. It is not something that can be seen easily, the velcro is easy to adjust as needed, and in my system it serves the purpose. |
Over the years, I have tried multiple types of spikes (including Audiopoints) into the concrete floor beneath my 175 lb main speakers (inc. stands), and also under my two 160 lb subs (inc. stands). About a year or two ago, I removed the spikes and tried using damped springs beneath the speakers and subs, and I found the springs to be an improvement. Most recently, I have switched to using Herbie's Giant Fat Gliders both for convenience and stability, and I have not perceived any sonic detriment compared to using the springs. After looking at this thread, I put the springs back under my speakers just for fun and found that I actually like the sound of the Herbie's Giant Fat Gliders better, I know...blasphemy, right? What would Max Townshend say? Springs, sorbothane, silicone, or Herbie's dBNeutralizer all provide some type of elastic damping and isolation. To me, the Herbie's products resulted in slightly fuller sounding body and better bass/dynamics, while the spring supported speakers sounded slightly thinner. The difference was noticeable but not substantial, and not as apparent as changing from spikes to springs. Maybe the differences I heard were the result of vibrational feedback or some slight distortion, but to me it doesn't really matter because it sounded better. FWIW, both the springs and the Herbie's products sat directly on commercial grade carpet over a dense commercial grade foam pad, over a concrete slab on grade. With either solution, over time the carpet and mat became quite compressed at the contact points. YMMV |
I for one am certainly all about "becoming one with the understanding of worldly functions" which is why I am deeply shocked to learn that the decoupling solution I am using under my speakers is "based on theorems or storyboarding marketers." Simply a "baseless opinion rendered by marketers, accessory salespeople, and audio reviewers" that is "taking you aboard the mystical Ripley’s train." Robert, believe it or not, you are trying too hard. |
Hello Robert – You are correct, "decoupling" implies totally separating two systems. The proper term would probably be “damping” but this is one of those industry slang issues. Decoupling is commonly used in the soundproofing and audio products industries and has been adopted by manufacturers, industry spokespeople, and audiophiles on these forums. Damping indicates the dissipation of vibrational energy, implying some portion of the energy entering a system is absorbed and ultimately changed to another form of energy such as heat, resulting in a reduction of the vibrational energy transmitted between the two systems. This more accurately describes what happens when elastomeric materials are used between speakers and the floor. The term "isolation" is sometimes used when referring to mass-loaded spring damping systems. These types of vibration dissipation systems are prevalent in the automotive and machine industries. As with many things related to this audio hobby, decades of point-proving and arguing have not determined a clear “winner.” Audiophiles are inundated by manufacturers clamoring about how their products are “the best” and frequently using pseudo-science and marketing psychology to influence purchasing decisions. At some point, all arguing aside, it comes down to a comment I recently read on a different thread, to paraphrase, “buy and listen to what you like.” |
Even with springs, damping and resonances play a role in the effectiveness. Robert's points, Max's springs, Herbie's elastomers, or the NHL's pucks will each perform differently wrt the transmissibility, amplitude, and frequencies of vibrations from one system (the speaker) to the other (the floor), or the other way around. The audibility and effect on the resulting sound of an audio system will be unique to each system and room. It is no surprise that there is no consensus here on what sounds best. |