You should also add Polycrystal to your list. I'm perfectly happy with mine although I did not A/B with the items on your list.
Be real clear about the Sistrum products/Audiopoints and their team. They are in the business of resonance transference. That's coupling not isolating/decoupling. Now that you know that: couple. Go on their website to read all about coupling, the benefits, and the contrasts to decoupling/isolating. You'll never go back to those "isolating" thoughts. Do your homework and let us know where you go. peace, warren
I am using Audio Resolution platforms under my VMPS speakers. They are similar to Symposium. They actually drain vibrations away from the cabinet, from the floor, AND from the cabinet itself.
I noticed a BIG difference in bass up to the lower mids when I put them in.
I've also heard them used very well in better-braced cabinets, like Totems and JM Lab's.
BTW, VERY good advice in general, Warrenh; always good to know about the different functions devices perform. I'd suggest reading the site he mentions, as well as the Symposium and Audio Resolution sites.
Thanks for the responses. I am wondering if anyone can speak of A/B direct comparisons for these products. Speakers are an interesting problem, perhaps because they are designed to resonate. I would think that isolating them on ball bearings would degrade the sound, being that they are more free to move in the horizontal plane. I know that testimonial and others experience would suggest this not to be the case.
There are alot of very long threads on the isolation vs. coupling theory. I thought this thread would be useful because it pertains specifically to speakers. I don't have the time or money to try all the different approaches. I know that some have put alot of thought and time into this stuff, and I wanted to learn from their direct experiences.
More specifically, I am wondering if anyone has experience with the Mana speaker stands. I am going with Mana for the rest of my equipment.
I went throught the same ''search'' about a year ago.....I own a pair of Avalon Eclipe's and as a result of new Berber carpeting in my listening room, the spikes that were supplied by Avalon just didn't raise the speakers up off of the floor enough. Which can be a problem, it is my understanding that some of ''these'' floor standing speakers SHOULD NOT be raised up that high because of their design and the listening height. Comments on that would be apreciated, because I have heard that putting a slab of Polycrystal under them helps greatly .....Anyway, I believe that ''decoupling'' is the answer and I went with the 2'' Audipoints and they did improve the sound and seem to be the right height
I have to admit being a bit confused about this subject. I recently replaced the spikes on my Alon Circe's with a set of Walker Valid points and Resonance discs. The discs are sitting on a 3/4 inch piece of MDF which rests on carpet above a wood floor (basement below). The improvement has been substantial, which I attribute to the speaker not vibrating with the floor. In particular, the imaging is more precise and the bass is tighter. Musical details are clearer.
But I've been told different things about whether I should use a maple block below the speaker or a softer wood like redwood or pine. The theory for the latter is that the softer wood would remove more vibrations from the speaker.
My listening room is in a late 19th century house with suspended wood floors. The loudspeakers are sited upon 2" thick maple platforms which in turn sit on top of Aurios 1.2s. For a little over $500 it turned out to be a very worthwhile tweak.
Regarding coupling vs. decoupling, I don't see how if I solidly couple any object to another object how "energy" is only drained in one direction. Specifically, if I couple my speakers to the floor and the floor vibrates, then won't some of that vibration get transmitted into the speaker?
It seems to me that coupling might be best for certain applications, and isolating for others. I, too, have a suspended wood floor. In theory, it makes sense to couple the speakers to the floor in order to stabilize the speakers and prevent smearing and distortion of the waves. But since the floor is now vibrating via the speakers, perhaps the rest of the electronics should be isolated. I would think that the floor vibrations would be much more detrimental than the vibrations inherent from the power supply and electronic circuits.
Has anyone tried this approach? I would think that a device like Aurios would create unwanted lateral movement of a speaker backwards with each forward push of the diaphragm. This might lead to a loss of coherence and a detriment to speaker accuracy. And yet, many people writing glowingly of the Aurios.
Can someone help enlighten me?
Rtn1, I honestly don't know why the Aurios work so well under my speakers, I just know that they work. As I said earlier, my house is an old wooden structure with suspended wooden floors. The house vibrates from internal sources (HVAC and stereo) and external sources (I live a half mile from an interstate highway). In addition to the speakers I've placed my entire equipment rack on a maple platform placed on top of Aurios Pros. It's not a huge or dramatic upgrade, but it's definitely worth the money and effort. The Aurios produce a general cleaning up of the sound with a better presentation of low level information.
Rtn1, I also have suspended floor. I have tried both coupling and isolation. For my room, isolation is essential. When vibration from the speakers gets into the floor, a lot of terrible sounding grunge obscures the music. My existing rig sounds very nice, and the difference (compared to bare speakers sitting on floor) is astounding - the largest single improvement I have made to my system.
I started with points, then cones. I was astounded at the improvement these made (over no devices). I could still feel some vibration on the floor.
In effort to isolate further I tried sorbothane pads. Floor vibrated less, sound stage was deeper (than cones or points) background was a bit quieter. Down side is music was smeared somewhat and lacked "PRAT" and excitement.
Convinced that I needed a more linear device than sorbothane, I tried sash springs. Smearing was gone, but not soft enough to decouple - floor still vibrated.
Better that all of these as isolation device (which I have been using for about a year now) are bicycle inner tubes, partially inflated. These float the speaker off the floor, in a manner similar to turntable suspension.
My speakers are fairly heavy (about 100lb) and dead, so coupling is somewhat less important for me. If you need to couple (ground) your speakers *and* isolate them from the soft floor (two oposite concepts) you could try this: Use a heavy, stiff slab or platform (maple, granite, concrete, etc). Ground the speaker to the platform with cones (under speakers), then isolate the platform with innertubes or springs (under the platforms). Down side of innnertubes is you need to re-inflate them every few months, and some design consideration may be required to keep them from being "tippy."
Have fun experimenting, and tell us what worked for you...
My theory. There are at least two issues to deal with. Draining vibration out of the speaker or isolating the speaker from the floor.
Each is helpful in it's own way. But which is better depends on everything in the system.
If a speaker is inert enough on it's own, then isolating the speaker is better. This is because there is a feedback loop that exists between the speaker and the rest of the system. Draining vibration into the floor will send more vibration into the equipment via the floor.
On the other hand eliminating cabinet vibration by draining it out may work better on a speaker that isn't very inert.
Both methods can and will make an improvement, but I've found that isolation nets a more musical presentation to the music.
Spikes drain away mostly low frequencies, so spikes on a suspended wooden floors may cause you to lose bass to the floor.
Cones and granite, especially BDR cones tend to reflect vibration back into the speaker. (I'm not saying the overall sound didn't improve with their use).
But the use of Aurios, Stillpoints, Darumas, Vibrapods, HAL Tenderfoots not only eliminated some cabinet vibration, but isolated the speaker from the floor.
The result was not only much more low level resolution, but the presentation and spacial cues sound more believable. BDR cones and other cones flatten the soundstage by comparison.
Putting Vibrapods on BDR "those things" or granite made the use of BDR and granite more musical.
(Caveat: I'm a Stillpoints & Daruma dealer, but utilize all the above mentioned products when appropriate)
First thing is, you can't "isolate" the speakers. The speakers are a strongly vibrating component, and they cannot be isolated from themselves, ever. If you think the cabinets are "dead", the driver baskets and cones are vibrating like mad anyway.
The ONLY way to deal with a situation like this is by a well engineered vibration drain system such as the Sistrum speaker platforms, or the Audiopoints. I have tried both, and the Sistrum platforms exceed the Audiopoints, in terms of performance. They should, because they are the next step up, and they cost more than the Audiopoints. But they are significantly better.
ANY soft type of material like rubber blocks or the like, will allow slight movement of the speaker in a fore/aft axis, thereby smearing attack and dynamics and coherence by doppler. They will also eliminate the path for vibrations to exit, and they are doomed to circulate and re-circulate in the speaker.
I have a suspended floor, and the Sistrum Platforms and Audiopoints have made a remarkable improvment in sound, especially in the speakers.
Another interesting benefit, is that you get another db or two efficiency out of your speakers, because they are operating in a more efficient mode, when the vibrations are properly removed from the motor. This is not a joke, or exaggeration. This is a real increase in speaker efficiency, and I have experienced it for myself.
I recently left the confines of working for a retailer that sold Thiel speakers..I know from experience the Thiel's will improve as much as any speaker I have ever tried either the Audiopoints or the Sistrum platforms on. It is because of the Thiel cabinet mass and density that the improvement will be so large..It is imperative to match the proper size Audiopoint to the respective Thiel product..Again because of their mass and the great amount of excess energy that these very dense cabinets do store..Sistrum Sp101 platforms are what I personally use under my still almost Dunlavy SCIV's..Tom
Twl is correct. I too have measured an increase in spl when using the Sistrum of about 1.5 to 2db.. This was measured in the retail showroom with an Audiocontrol RTA..Oh and these are not isolation devices and if you were to try to dampen or isolate the Thiels they would only gain in bloat and blurr.Tom
This thread is of great interest to me currently. I have recently placed my 5As on a piece of MDF over the carpet on a large second floor listening room over the garage. I did this to help me move them around for purposes of testing. What I discovered is that the speakers had much more life in them on the MDF. The highs were much clearer and the vocals more magical. After listening for a couple of weeks, I put them back on the carpet in exactly the same position and the life was sucked back out.
I had previously believed that the speakers were best off coupled to the floor, and the 5As have cones which I assumed were coupling devices. Now I realize that for reasons I can't explain, the image is much better with a degree of isolation.
Let me also say that the cones may not have penetrated the thick carpet and pad very successfully.
Can anyone help here? Should I be considering a better isolation platform under the speakers? Or should I be cutting through the carpet to let the cones get to the subfloor? Can an of the Systrum technology help? I looked at their stands and I don't think they can mate to the botton of the 5A with its sub opening and grill.
Thanks for any help.
Isolation vs coupling...I won't go there. However, if you want to isolate, nothing is better than suspending the speakers from the ceiling. Chains or wire, and perhaps monofiliament fishing line works. For even better isolation (from the ceiling) you could use bungie cords. Cheap too.
With the boxes floating in space you get acoustic isolation as well as mechanical isolation. IMHO the acoustic part is usually most important.
I am most interested in what is going on here. When the speakers are spiked onto the floor, this should create the best path for resonant energy to depart (good), and this should increase the energy input into the floor which drives the natural floor resonance (bad). Putting the speakers on MDF over the carpet should reduce both the good and bad effects above. This is the dilemma.
I can notice this dramatic improvement when listening to a female vocal with delicate symbols and piano in the background. So there are no heavy bass notes that might be shaking the speakers or the floor. Also, for what it is worth, I can easily feel the floor resonate around 30HZ when conducting SPL measurements. However, the I have adjusted the subs in the 5As and have a smooth response from 20 to 160 HZ within +or- 3DB.
Yesterday I bought some heavy cutting boards to try under the speakers in place of the MDF. I am just trying to confirm what I am hearing with another material. I would like to try the Systrum platforms, but it would seem to raise the speakers up too high for proper listening. With regard to hanging the speakers on wires, these 5As weigh 185 lbs. each!
I spoke to Richard Vandersteen at CES about this and he doesn't like putting the speakers on MDF because he felt they would not be stable enough (movement front to back that would distort the image). His answer was to strengthen the floor from underneath.
I'm still trying to figure out where to go next. Thanks for your ideas.
Theaudiotweak...Enclosures should be solidly constructed of "dead" material, shaped so the panels don't vibrate, (cylinders are good), internally braced, and internally damped. If the top/sides of your enclosure vibrate, even glueing the bottom to a concrete floor wouldn't help.
Of course, the real answer is to get rid of the box entirely: go planar.
My listening room is in a formal living room with cathedral ceilings and a very strong WAF. I am just lucky to have it there at all! The decorator once came in and asked if I could push the speakers back into the corners. That got a lot of support from the other half. I am afraid hanging is out of the question or it would be my hanging!
I think you are on the right track to isolate your speakers from the floor. You might find better results with a platform which is more massive that MDF - granite, marble, or custom poured concrete (decorated with something of course). Your speakers should sit on this platform on three pointed feet. If you wish to get adventurous, do what I have done: use bicycle tires to float the platform (isolate) above the carpeted floor. I can give you details if you are interested.
Here are the issues, in order of importance as I see them:
1) You do not want your floors and walls vibrating. If they do, they will radiate sound which is very bad. You cannot avoid exciting floor/wall vibration from acoustic excitation, but you can reduce speaker mechanical vibration from exciting your floor. Please note we are not talking concrete slab floors here, we are talking about wood floor over joists.
2) You do want the mechanical connection, between speaker and floor (or for that matter, all the rest of your system) to be linear. Rattles must be avoided as they destroy music and generate unwanted noise. Also you do not want the mechanical connection to be modulated by the music (or associated speaker vibration). If the connection is through a squishy or rubbery material, this is also less than optimum because the material is not linear, and music loses its pace and timing.
3) You do not want the speaker box to vibrate - only the driver diaphram(s). This of course is a distinguishing feature of loudspeaker designs, the degree to which cabinets vibrate and radiate sound, or excite the floor beneath them.
If you have a concrete floor, anchoring the speakers to the floor addresses item 3. If your floor can vibrate, then item 1 is likely of much greater importance.
Using cone or points under the speakers can actually help all three of these. Transfer to the floor (1) is reduced because the interface points of contact are limited to corners and edges of the cabinet where box modal vibration is minimized. The linearity (2) of the interface is improved. And this usually reduces at least the lowest frequency motion of the box (3)to greater or lesser degree.
In my experience, while using cones under my speakers provided a huge improvement in sound quality (over speakers on bare floor), there was still significant floor and wall vibration which I could hear and also feel with my hands and ear (against the floor). The sound improved even further when I isolated the speakers from the floor. I tried sorbothane, rubber feet, stainless steel sash springs, and finally bicycle tire "air springs."
In your case, you could get some of the best of both worlds ("coupling" vs "isolation") if your speakers sit on cones on (coupled to) a massive platform. The platform (isolated from the floor) sits on soft linear springs.
If you have children or pets, or concern over the 5As being "tipsy", then maybe the air springs are not for you. In my case, after hearing the difference, I am more than willing to explain to visitors why my speakers are "floating" like a turntable and bounce or rock at a few Hertz when you bump them.
Please report your experiences so we all can learn from them.
You have lost efficiency by hanging the speaker in air.The natural tendency is for the cone to move back and forth. The back emf is swinging the speaker.. The front force of the cone is being cancelled by the back emf. Who wants that? An athlete can get off the line faster and with more stability if they have spiked shoes. Cabinet, no matter how dense will store energy.In fact the more dense the cabinet the more resonant noise it can hold.So it is even more important to direct couple these type of massive enclosures. The noise has to be given a way out or it will pollute the music..Tom
Theaudiotweak...The natural period of swinging object (of any weight) on a chain as short as 40 inches is one second, not an audible frequency. The force exerted due to cone motion (its mass and air resistance) is a few ounces, and won't move a 100 pound speaker system enough to be detected. So the idea that the speakers will be swinging around wildly when they play is only believed by those who have never experimented with this setup.
Spikes, or other means of mechanically coupling the bottom panel of a speaker box to the floor may damp vibration of that bottom panel, but will do nothing for the front, back sides and top. Vibrational energy does not need to be "drained" like a fluid from the box. Damping material in and on the box absorbs the vibration which produces heat. The heat does indeed escape from the box, but you can't hear heat.
I agree with you that one would like the speaker box to not move, and that the reaction force on a woofer (or other driver) motor/basket can be very large - many pounds. This force must be reacted by the cabinet and possibly the floor. But the cabinet is not only a mass at audio frequencies, but has stiffness and modes of vibration. While the cabinet-to-driver mass ratio can be perhaps 1000:1, the cabinet can still end up vibrating significantly at certain frequencies.
This is not a simple problem, and there is not one solution which is best for everyone. For me it did help a lot to "ground" my speakers on points to the floor - but isolation worked even better. I have a flexible wood floor. Perhaps you have a concrete floor?
Sir you are mistaken. The back and forth motion of a 100lb speaker on a carpeted floor while reproducing music is greater than the total excursion of the tweeter in that very same speaker. So much for proper phase response and time alignment..And sound is like fluid. Unwanted energy needs an exit point..Tom
That is a good point about tweeter motion. This is why some speaker designs decouple the tweeter from the rest of the cabinet, rather than hard mount it to the front baffle.
Still, due to cabinet modes of vibration, even with base of cabinet "fixed" to floor, there could still be a lot of vibration of the tweeter (due to woofer-induced cabinet motion). We cannot guarantee that for all speakers, on all floors, that this product or that product will provide the best solution. Also, many times one thing gets better while another thing gets worse! That is what makes this hobby so interesting...
Charlie you are correct. The cabinet is in motion and stores energy and that counteracts the motion of the drivers we only wish to hear. That is why I use the Sistrum stands under all my components as well as speakers. The designer makes claims that I agree with. That their products provide geometry and materials which expedite an speed to ground, resonant energy.. They made a huge performance gain in my system..Tom
Theaudiotweak...Have you measured, or even calculated, the motion. I am not sure that you are correct about that. But so what? Any rocking motion of a 100 pound object will be at a very low frequency. So the tweeter moves around a bit. Well, so does the flute, or whatever other instrument is making the recorded sound. No one requires musicians to clamp their instruments into a rigid mount when they play them. Do you clamp your ears into position when you listen?
Again I point out that vibrational energy is converted to heat by damping material. That's its "exit".
So we agree to disagree. :)
Just curious to hear what you ended up doing with your Thiels. I have a pair of CS3.6's, and have the tweak bug big time. The Sistrum platforms are getting some great reviews, but I am wondering how they would fare in a house with a very active 2 year old, who is known to occassionally run into my Thiels (which don't budge, and lucky for him, he somehow stays away from the cones!). And how would the Sistrum platforms connect to the bottom of the 3.6's (which have a raised box-like structure on the bottom)? Do their top spikes line up with the holes for the stock spikes?
On a related note, are there any replacement spikes that would fit in the stock holes but do a better job?
The fact that the support and interface we place under a speaker perceptively changes the sound clearly illustrates the insidious nature of vibration as it relates to an audio system. Almost every aspect of sound reproduction - tonality, spatiality, dynamics, coherence, etc. - is compromised by unwanted vibrational energy. That is the result of a disturbance in the relationship between frequency, amplitude and phase of the original signal that the audio system is reproducing.
As the speaker drivers are radiating acoustic energy into the room (the energy that we want - music) they are also sending energy into the speaker cabinet because of air pressure from the inward motion of the cone and by conducted energy through the frame and mounting flange which becomes unwanted stored energy (USE). This USE causes the cabinet walls, the crossover components, the connected speaker cable, etc. to vibrate (the drivers are also subject to compromise by their own vibrational energy that they've sent into the cabinet that is then reflected back towards them after a delay in time). The cabinet vibration has the most consequence towards corrupting the speaker's performance. If we were able to quiet the driver's acoustic output into the room and just hear the result of the cabinet walls vibrating I think we would be shocked as to just how much audible acoustic energy the cabinet would be radiating! THIS version of the audio signal would have a different frequency balance than the driver's output (it would sound muffled being dominated by the primary and secondary resonance frequencies of the cabinet) it would be lower in amplitude (but not uniformly lower because of the non-linear nature of the cabinet materials) and would be delayed in time (the amount of time it would take for the energy to leave the drivers, be absorbed by the cabinet and then be released into the air) thus affecting phase integrity. If we think about this 'smeared' version of the signal (which contains corrupted frequency, amplitude and phase) being mixed back into the original signal it is no wonder that USE significantly affects the reproduction and that altering the USE has an audible effect!
Now, just imagine if we make a significant reduction of USE in the speaker cabinet. The amount of audible difference would be profound. Placing high mass on top of the speaker cabinet will significantly increase the resonance frequency (a good thing) and decrease the amplitude (also a good thing) of the top panel. The weight load will then be translated onto the side panels with a related change in their resonance frequencies. Furthermore, the added mass will more effectively couple the speaker bottom to the top plate of the speaker support, the floor or more suitably to a high-mass high-absorption platform so the USE can be drained from the speaker cabinet.
If we used laser infrarometry to measure the displacement of the speaker panel we would see a noticeable reduction in displacement (vibration) when high mass is set on top. In addition, if a high-mass high-absorption platform is placed under the speaker, this multi-stage vibration control system forces the speaker to be more effective in its main task of reproducing music - the drivers do not waste their energy in making the cabinet or internal parts vibrate because the cabinet is far more resistant to displacement. The drivers have no choice but to use their energy more efficiently in creating music.
The most effective method for supporting a speaker would be a high mass element on top of the cabinet, a high-mass high-absorption platform directly under the speaker (on top of a rigid and strong stand for a mini-monitor) and a pneumatic base on the floor to decouple the speaker's energy from entering the floor and being transmitted to the equipment rack. This configuration is highly successful in eliciting the peak performance from the speaker without a redesign of the cabinet or the component parts.
The other components in an audio system will also benefit by a reduction of USE in their chassis. Besides speakers, turntables exhibit the largest degree of improvement by proper vibration control. Since they are electro-mechanical devices it is almost intuitive to us that this be so but the purely electronic devices also benefit: tubes are microphonic, the master and sub-clocks (which are based on oscillating crystals) in digital devices are affected, a spinning disc inside a digital player will exhibit non-linear movement, all component parts (transistors, ICs, capacitors, resistors, wire, diodes, etc.) that process the signal become microphonic, motors, fans and buzzing transformers induce vibration into surrounding parts, and the list goes on.
What are the sonic results of vibration contamination? As we discussed, frequency, amplitude and phase are corrupted. Frequency balance is skewed: one portion of the spectrum is highlighted or diminished as compared with another. Brightness may increase, midrange may become too forward, bass may bloat and become ill defined. Amplitude of the signal is changed: the dynamic range of an instrument and indeed the dynamic relationships between the instruments are altered. Phase integrity of the signal is deteriorated: the spatial relationship of the instrument with its environment and the spatial relationships between the instruments are altered. In fact, frequency, amplitude and phase are interrelated and changing any one affects the other two. If all three are affected at the same time (by the presence of unwanted vibration) the resulting cacophony significantly reduces the ability of the system to convey what is actually contained in the recording - and that's what audio is all about. Not just what sounds pleasing because it makes someone feel fuzzy all over but what is musically and emotionally fulfilling because it reflects the actual sound of the instruments as they have been captured in the recording.
When we eliminate the sonic results of vibration contamination we more accurately hear what the individual components in a system are doing. It is possible that these results might be misinterpreted by some individuals. For example: if a speaker is providing excess out-of-phase elements the size of the soundfield might INCREASE beyond what is actually in the recording. Bigger is not always. This individual will have adjusted speaker placement and acoustic room treatment based on this exaggerated sonic view of the soundfield. Once the out-of-phase elements are properly controlled by reducing vibration the size of the soundfield may become smaller in this incorrect set-up and the listener may say, "Oh, this is not as good as it was before because things are not as large." What they should be doing is reevaluating speaker position and room treatment to optimize the now correctly operating speaker. Once that is accomplished they will find that not only is the soundfield as large, if not larger than before, but the instruments are in proper relationship with one another and ambience is cohesive instead of exaggerated. Frequency changes can also be misinterpreted: in a vibration plagued system a too forward midrange during transients is a typical symptom. Some people might misinterpret this as the system exhibiting "good presence" or a forward brightness region is often described erroneously by some listeners as "good detail". The removal of the vibration will eliminate these effects. Some may feel at first, that the removal of these exaggerated artifacts is a step backward in reproduction, but what they are hearing in the now vibration free system are the possible cumulative effects of previous tweaking and/or component choices made with a vibration drenched palette. Once the problems caused by USE are removed some system choices may need to be reevaluated.
Bright Star Audio
Disclaimer: I am a manufacturer of vibration control products.