Given that a CD Player or Transport has quite a bit of internally generated energy from the motor, is it best ti deal with vibration issues by coupling the player to a surface with spikes or cones? or decouple the player from the surface beneath it with spongy materials? Any consensus on the best approach here?
You will not get a consensus here. FWIW IMHO things like sorbothane are far more efficient in absorbing energy and does so much closer to the source of the vibration than other things used. Conversely transmitting the vibrations thru metal cones, etc, to other hard surfaces only delays the dissipation thereby aggregating its effects. All of this of course depends on whether you believe the 'drain theory' is more than just a theory. Consider that some believe that the vibration when it occurs does the damage to the sound at that time and there is no real remedy. I suppose if your component can actually store (build up) the effect of the vibrations it might be important. But if it can actually store energy at what point would the stored energy reach a point of destruction? Another question, when we discuss the 'drain theory' does it make any difference at what frequency the resonance (vibration) occurs? If so, does that affect the nature of the materiel you use to help dissipate the resonance?
This is why you will get no consensus. Hell, I can't even agree with myself! :-)
By the way, I am currenty using Herbie's Tenderfeet which isolate from the supporting surface (3" Maplewood shelves on a all Maplewood stand with sits on washing machine/ imdustrial isolation pads to minimize floor based vibration. I suppose if isolation is the technique used microscopes from vibration that is proabably worth noting given that vibration would be very obvious and is not based on theories used audio accessories vendors to convince audiophiles. I do realize though, how silly the search for consensus on this topic is - worse than asking SS or tubes.....
I was just checking this tonight, my CD player is on a Star Sound rack equipped with large cones for coupling to units to the rack and draining vibrations quickly. But I got a better result putting the CD player on a marble tile resting on 3 tungsten carbide ball bearing resting on 3 FIM saucers. I sell both so not partial. This result applies ONLY to my system at the present time.
I use both approaches in my system. My belief is that coupling (i.e. draining) works best with speakers, while decoupling (i.e. isolating) works best with just about everything else. That is 50% science, 50% hunch.
Some may find this discussion draining and isolating at the same time;-) This is not just an attempt at a little dark holiday humor, but actually a preview of my experience described below.
I have tried both approaches with my CDP and find: 1. there is a clear difference in sound, and 2. for me at least, draining clearly sounds better. But wait, I also use isolation...
I have my CDP resting on hardwood blocks on a very substantial maple platform, bypassing the stock rubber feet in an effort to "drain" vibrations away from the CDP and into the heavy platform below. Placement of the blocks makes a difference, and I have found placing one directly under the transformer is critical to improving performance. But I then "isolate" the platform from the supporting shelf and the rest of the room with sorbothane dots to "protect" the CDP-block-platform "system" from external vibrations resulting from, among other things, the occasional loud music passage.
I have tried pretty much every permutation of these components and some others, and like the sound of my current arrangement best. I would describe the CDP sound as relatively more clear, articulated, dynamic and fast. In contrast with the stock rubber feat or sorbothane directly under the player, the sound turns soft and a bit mushy. It is actually surprising how much difference these vibration control measures make - it is not in the least bit subtle. I use the same approach with my turntable that I do with my CDP, but find no noticable advantage with isolating or draining vibration from my SS amp and tuner.
My speakers are also on platforms, but these are on blocks, spikes or Bluetack directly on the floor in an attempt to get the vibration out of those boxes as quickly and thoroughly as possible.
As for the microscope analogy - I worked with microscopes for many years, and yes, vibration is the enemy. But purely optical microscopes do not generate any internal vibration of their own, so there is no need to "drain" it away from the lenses - it is all about keeping vibration out and isolation is the name of the game. Lights are often attached or driven by outboard transformers to keep any vibrations they might generate away from the scope body. Scanning electron microscopes are a different story, and one I am less familiar with. But I digress...
I haven't done the vibrapods under my Oppo BDP-83 but I did do mass loading on top of the player. 2 5 lb plate weights along with a sheet of Acoustimat under the weights. It definitely helped with the vibration when the BDP-83 is playing any kind of Blu Ray movie or CD/SACD.
I go with the ones that say coupling could be good or bad. Sometimes the shelf could vibrate more,and cause more problems.Coupling to something with more mass,or isolation, may help.I think it's situation dependent.
I have 4 players in my set-up. So from the player down this is the order they are in. I place all 4 players with there stock feet on a 15x20x2in thick Maple cutting board. I then put 3 roller bloc Jr. under the cutting board, two in the front one in the back center position. The roller bloc Jr. sit on top of another Maple cutting board the same size. This second maple cutting board sit on top of 3 rubber/cork squares like the one Mapleshade sell. The rubber/cork squares are place 1 in front center position and two in the back on my equipment rack shelve. I have two racks and both speakers that I use this 2 maple platform on. I removed the 1/4 20 brass spikes that came with the speakers and replaced them Audio-Point brass spikes which were an improvement. The real jump came when I replaced the Audio-Points with the 1/2 inch grade 25 Tungsten Carbide ball, which fit perfectly in the hole left by removing the spike cones. That was over 6 years ago. I have not looked back since. And as of today, I don't have 1 cone or spike in my system. It is MY belief that Tungsten Carbide ball work better than spikes when using the maple cutting boards. Please remember this is just MY opinion base on my fooling around with spikes ,cones and metal balls for 7yrs in my system only.
Placing my friend's TT directly on the rack, it played fine. Putting cones under certainly seemed to improve the sound. Flipping them upside down, putting the cones 'point up' caused it to mistrack on some passages. This, to me, suggests "draining" does occur. By the way, the cones were short, wide and made of aluminum. There are two sources of vibration: Internally generated, and externally generated (sound). I would think that using something like sorbothane would isolate. But what about vibration from a component itself, or picked up from sound waves? How about both approaches? Cones under a component that has damping pads/and or weight, sitting on or "draining into" a platform that absorbs and is sitting on sorbothane feet to isolate. Someday I plan on trying something like this under my TT.
I sometimes wonder why I don't simply don't trust Ed Meitner to know what kind of feet to put on his players for good performance - the latest generation does appear to have given some more serious thought to design of the footers. Which did not stop me from putting 3 brass pucks, with a Sorbathane layer, on top of the player for mass loading and Herbie's Tenderfeet underneath. Not sure it improves anything as it is a pretty solid player to begin with, but it looks nice and wasn't too expensive. I get the sense that for every isolationist there will be an equally vociferous drainer - both with "happy" results.
OK, I support the info from Mapleshade. You drain from the top and you don't stop till you get to the bottom. Every component, every shelf has to work to drain the vibration from the whole and into the floor or you defeat the benefit. If you like putting weight on top of the components that's fine but it won't give you the full benefit unless you drain what's been created by the system components.
One of the best tweaks I've used for my tone arm are the Nano Mounts and record clamp system from Mapleshade. It's not easy to put micro sized triple points between the cartridge and tonearm and also the tonearm base and arm board but it is defitely worth it (this is draining). And by the way, loosen the screws on your cartridge till they just barely tighten the cart to tonearm. They really don't need to torqued to stay in place and it deadens the sound. And get some brass screws too.
I use OHAUS brass weights on top of all 4 players in my system. The weights are 20g(2),50g(1),100g(1). For what ever reason the brass weights work best in my system on the front right(3 players) and front left(1 player) of the units. One odd finding is that on all 4 players they work best on the front opposite side of the units power cord. Example: 3 of my players have power cords on the back left of the unit. On those players the brass weights sound best on the front right. It is just the opposite with the one player that has the power cord on the back right of the player. The brass weight sounds best on the front left. Don't know if this just a coincidence. But it is consistent with all my players. I know what some of you are thinking, what would happen if my power cord was dead center in the back of my unit, would it go both ways?
Your tiny electronic vibrations in your player likely isn't going to be in a frequency you can hear, but I doubt that would convince you. The science behind coupling is to make the entire system as heavy as possible -- with more mass, the resonant frequency lowers. This should actually be harmful on your audio rack unless your rack is weighed down with a hundred pounds of sand (think metal speaker stands) if the resonant frequency is within audible range.
Decoupling -- viscoelastic material such as sorbothane actually absorbs some of these vibrations and turn them into heat. This is mechanical engineering 101, for more info, look up the "spring-dashpot" model.
I think in the medical, HVAC, etc. industries where vibration must be stopped to reduce noise or because of sensitive equipment, decoupling is most likely to be used. Coupling will pass vibrations onto other components where it will be harder to control; the idea is the control vibrations at the source, and that means using springs and hydraulic shocks in the worst cases to turn as much vibration into heat as possible.
The problem with coupling is it works both ways, regardless of the direction of the spike. Draining vibrations could just as well introduce external vibrations into the system, such as from the woofer, road noise...
Rakuennow -In my experience, cones "drain" in one direction. Try putting "spikes" or cones upside down under a Turntable as I described above if you doubt it. My guess is that ball bearings isolate better as opposed to "draining". If the cones drain the vibration into a platform, chances are the materials will absorb at least some of the vibration. It would take a carefully engineered rack to transmit all that vibration to other shelves. Also, I believe most people will respect the weight limits of the rack they choose to use. Thanks for the reminder that viscoelastic materials turn mechanical energy into heat. Good to know. In audio, one of the sources of vibration is the very thing you are generating- the sound. This poses problems that are unique in application. Even if you doubt the significance of vibration control for most components, you must see the benefits for analog equipment.
CD players are also mechanical devices as they depend on reading a moving disc so vibration will have an effect on them. Note the effort by some of the top players to deal with vibration by floating the components on the chassis. I have my TT and CD on roller bearings and the rest on the Star Sound cones. The thing to bear in mind is that ALL of these things "work", i.e. change the sound. Which is best varies from system to system and owner to owner. And from time to time, I have changed my mind about which I prefer more than once.
Stanwall, I think you hit the nail on the head when you say 'works' means changing the sound. Good point!
I notice one fella sez he likes his phono cartridges when they are not torqued too on the headshell very tightly. Obviously he likes the sound of a little bit of added resonance. Some folks seem to like tubes that are slightly micro phonic which will also convey some extra noise.
So IMHO, it is not so much about what eliminates the effect of resonances in your systems but how you can alter the resonances and tune your system to get your preferred sonics.
The results (positive or negative) from using ANY form of vibration control on an ANY component will vary according to the particular design of the model, system synergy/tuning and personal taste. The only way to determine what will work depends on experimentation. At a dealership, I heard the use of such devices under various CD players and there was no single product that was consistently helpful under all models. For example, the Symposium Ultra shelf (vibration drain) is incredibly effective at what it is designed to do. Use under some CD players resulted in greater clarity, detail and more obvious microdynamic contrast. But, under an Aero Capitole player, the sound became WAY too dry and lean. Under my own player (Naim CD555) the platform had very little effect. I've also done some experimenting with footers and Symposium rollerballs, etc. and I also find the same thing--sometimes the result is good, sometimes not. I don't think there is any kind of consistent "right" approach.
The same is true with all other components. While the most common approach with speaker is to couple the speaker/stand to the floor with spikes, I often find alternative, decoupled approach, works better on suspended, wooden floors. My speakers sit on Symposium Ultra shelves which have a soft inner core that drains/absorbs vibration from the speaker. I am just guessing, but, this probably keeps the floor itself from acting like a sounding board. Again, only experimentation will give a meaningful answer.
Newbee, I believe it is all engineering and physics. Everything affecting the sound of our systems can be evaluated and modeled using engineering laws, mechanics of materials, and psychoacoustics. What's left is psychology and personal preference. There are variables in that every designer has their own take on how the engineering affects the sound, which factors are most important when trying to achieve sonic excellence at a price point, and trying to guess at the personal preferences of their customers. Our personal preference can be affected both by the sonic traits we each associate with enjoyment, and also by other factors such as appearance and perceived value. It gets more interesting when we audiophiles are Jedi mind tricked by manufacturers who use science for profit by explaining just enough of something to make us think their product uses "new technology that is better than anything before" or by appealing to our visual perceptions by offering things like thicker cables that must be better than thinner ones, or new age materials like carbon fiber on our outlet covers. I suspect we also spend quite a bit of money for things that may make a positive difference that can be explained scientifically, but perhaps not a sonically significant difference. With regards to vibrations, I cannot argue with the practice of trying a bunch of stuff and using what you like best. Just because it isn't scientific doesn't mean it can't be fun.
I use Herbie's Tendefeet under everything electronic. Cones will "drain" in the vertical plane while the Tenderfeet "drain" and absorb in all planes from the point of contact. Can't say you'll have the same results but it works for me.
Playpen, The nanomounts are placed (ie. glued) onto the cartridge and then the cartridge is attached to the tonearm. The triple points are on the cart with the single point touching the tonearm (you must not overtighten the cart to the tonearm). This is just like the system you currently use to drain vibration from your Rega's plinth only in miniature. With the tonearm you place the nanomounts between the base and the arm mounting board. This is not an easy process but I felt it improved the sound clearity (ie. reduced resonance)on my Clearaudio Champion Level Two and Unify Tonearm/ Ortofon 2M Black.
If you like your present rig and plan to stay with the tonearm I believe the nanomount system is worth it. I've tried tweaks from setup guru's over the years and I have had the best results from Pierre Sprey of Mapleshade. He has many no cost tweaks on the website and some that you can purchase. I believe that before you spend alot of money on a new cart you should try this solution and it has a money back guarantee. Mapleshaderecords.com
I have recently coupled my system so that all components are tied to my rack to drain and WOW it does make a serious improvement. It's called RTS Coupling from Audio Horizons. Over they last 20 years I have tried many ways of controlling vibrations including Herbies, Nordost, Eichman Toppers and many more. The improvement from coupling is 20 fold to any other device I have ever used. I only listen to CD's and what I have noticed is more micro information, more body, sense of ease, more dynamics, more of everything good and nothing bad. A very inexpensive way of making a HUGE improvement to any system.
Addressing your initial question about isolating/damping CDP against vibratipn, I do both. In the few CDPs over the past 23 years, Ive dampened the chassis with rope caulk or Mortite. I started using Mortite on the underside of my Denon t-t back in the late 70s with good results, so I was anxious to use that on the CDP. IME, all aspects of the sound improved. I also isolate the CDP using Symposium Rollerblocks which further improve the sonics.
Try the rope caulk. It will cost less than $10 to do your whole player.if you dont like the sonics,simply remove it.
So many factors, unknowns, and interactions -- it seems like only trial and error can produce satisfactory answers. The goal is to prevent vibrations at the resonant frequencies that most harm a piece of equipment's performance from affecting that piece, regardless of whether those vibrations are generated internally or externally, right? So, to start with, how many of us know what those harmful frequencies are with regard to most of our equipment? And then, choosing an overall isolation philosophy versus a distribution philosophy probably means choosing some tradeoff between goods and evils, which of course is normal with this hobby.
I use the word distribution instead of coupling because it strikes me as a more worthy opposite to the word isolation in terms of indicating what we're trying to accomplish. It indicates that we're trying, through coupling techniques, to make our piece of equipment become part of a larger system whose overall vibrational characteristics are more favorable in terms of the piece of equipment's performance. We might be trying to bind our piece of equipment to a shelf, a rack, the floor, or even to bedrock. (I'm in the camp of those who think "draining" is a misleading term.)
Mass-loading, which has been brought up almost as a third approach, falls into the distribution approach, both by changing the immediate characteristics of the piece of equipment's case and by increasing the effectiveness of the coupling between the piece of equipment and the shelf underneath and who knows what beyond.
Notice that coupling has to play a role no matter which of the approaches, isolation or distribution, we (think we) are taking. If we're using isolating footers, we have to make sure the footers make really good contact with the equipment. Luckily, this seems to be a built-in characteristic of most squishy footers. Let's say that for isolation we're putting a heavy sandbox or lightweight Neuance-type shelf under the equipment. Then we might want to choose footers for the piece of equipment that (we imagine to) have good coupling characteristics. Otherwise, we might not realize the benefit of all the trouble we've gone to to provide a special shelf for the equipment.
Of course, it's all a bunch of compromises anyway, and it may be that in the case of any particular piece of equipment, the designer has chosen a compromise solution that's as good as any we'll come up with. Sometimes it strikes me like trying in the stock market to beat an index fund, but actually, the odds are much better here, since we have some degree of control over our equipment and rooms.
Clearly, there is some good we may be able to do through our obsessions. That is, some solutions do reduce distortion that we are able to hear. After that, there is a whole bunch of sound tuning that we can do to indulge our infernal restlessness.
Anyway, various people have put forth some useful concepts about what vibration control approaches work best for particular parts of the system. In practice, since vibration is attacking from both land and air, as well as, I guess, from within, probably neither isolation or distribution is theoretically a perfect answer. But we can't execute either strategy perfectly, either, so it's all good! Random trial and error may be as effective a strategy as one of the more coherent conceptual approaches, but it probably doesn't make us feel as good about ourselves, which is probably another inherent goal of the hobby, eh?
Pubul- I never damped a tube amp chassis, only CDPs and pre-amps. I also packed rope caulk around the transport mechanism.
With amps, I usually try to drain out vibration via cones onto a constrained layer platform (Symposium),especially when the Ps and transformers are mounted on the bottom plate of the component chassis.
This is really something you have to experiment with.
I have often asked this question myself. Currently I'm working both sides of the fence so to speak. I have a Mapleshade Samson 4 shelf rack with Heavyfeet thick carpet spikes penetrating through the carpet to the concrete floor below. My amp and preamp both use the Mapleshade model for draining vibration; a maple platform supported by their Isoblocks with cones mounted rigidly to the chassis. My CD player sits on Herbies IsoCups and my DAC is on Herbies Tenderfeet. I also use mass loading in several different applications: HRS damping plates on top of my amp, preamp, and CDP, Mapleshade Heavy Hats sitting on Herbies Grungebuster Dots are on my speakers and power conditioner. This is definitely not my first go round at vibration control, and I'm pretty happy with the present configuration. I have noticed that the Samson rack is picking up a significant amount of vibration from the floor below. It appears to be 60 cycle hum possibly from an improperly isolated distribution transformer in a nearby electric room. It seemed to me that much more vibration was being transmitted TO the rack than what was being drained FROM it. I contacted Mapleshade with this question and got the following answer: "1. Back in 1986, I did a very careful experiment that proved conclusively that internally-generated vibrations in components have a major degrading effect on sound while external vibrations (in the floor and in the air) have a negligible effect. This is the whole basis of our approach to vibration control.
2. The Samson rack's function is to drain vibration out of every component into the maple shelves and from there down into the floor via the most direct path. Isolating the rack would simply block the vibration path into the floor.
3. Steady-state vibrations or random noise vibrations that are not correlated with the music have essentially no effect on sound quality (the same is true for electronic noise). It is vibrations that are correlated with the music that seriously degrade sound.
By the way, testing for vibration problems by feeling vibrations (or measuring them with accelerometers) in the component--or by rapping on it (as audiophiles do instinctively with turntables and speaker enclosures) is a total waste of time and never correlates with what you hear. The only useful way to "measure" vibration problems is to change something in the vibration path and then, by listening to your standard music test tracks, determine whether the change improved or worsened the sound of the music. Nothing else works" I heard a very good point brought up in another forum regarding the draining of vibrations: does the draining occur before or after the detremental effects are felt? Think about that one for a while...
Using rigid devices to "drain" vibration is mostly audiophile voodoo, IMHO, and mainly espoused by those that sell products designed to "drain". Honestly, as someone who has tweaked ad nauseum with all kinds of isolation devices over the years, I am convinced that this is one of the most over-hyped areas of this hobby and one of the least beneficial expenditures of an audiophiles dollars (exceeded only by jitter reduction devices and followed closely by AC conditioning devices). I suppose a brass footer, for example, that reduces to a small point may help (or seem to), simply because it reduces the contact area between a component and its point of contact with the rack. On the other hand, absorbing material used as footers will definitely help prevent the vibrations generated by component from transferring to the rack, but obviously does not stop the source of vibration within the component. To stop the source of the internal vibration, you will have to open the component and damp the offending source, such as a CD transport or power supply. With well built and designed gear (which often equates to "heavy"), I haven't found much need for either internal or external damping. I put my gear on inexpensive absorbent rubber footers (Herbies) and after having thrown lots of money down the rabbit hole, I've discovered there isn't a true need for anything more.
Its as if your gear in a mechanical sense is all cap coupled from the inside to the outside environment and back again. In some worlds cap coupled is the color of the day. So called isolation devices are indeed crayons from some kids tool box. Tom
Solid base under components , solid bass response . Balls , cones , springs , spikes , under gear , better detail , air . Thats not a consensus just an observation . Ya right a consensus on an audio forum ? ! ? ! Carbon fiber cones and platform makes my transport happy , but my A.R.C Dac 8 insists on direct contact with a heavy wood base . Go figure .
Its as if your gear in a mechanical sense is all cap coupled from the inside to the outside environment and back again. In some worlds cap coupled is the color of the day. So called isolation devices are indeed crayons from some kids tool box. Tom
So called mechanical isolation is a kin to cap coupling in electronics. Cap design and their material makeup are coloration devices as are materials and geometry chosen to make so called isolation devices. All of these are filters of sorts and there is no such thing as a perfect filter anymore than isolation is perfect or even possible except in the absence of matter. Because isolation is not possible...I have in my system applied extensive resonance grounding methods to all my components. I have dis carded all soft materials and replaced them with hard materials that are then mechanically grounded to the higher mass of the floor. Mechanical resonance drain..I find these methods very realistic and musical..
I use both methods and they both work, but do not sound the same. I have not had good results with rubber or Sorbathane [sp?] to the same degree. For instance when I took the rubber feet off VPI turntable motors and replaced them with small brass cones it improved the sound; also replaceing the stock feet with their rubber washers with solid brass cones was a large improvement.