Isolation vs. Absorbtion

Great advice Dakay. Thanks a bunch. - Dan

PS: Many people would aslo just place the Pods or the EAR's directly between the shelf and the player for starters if they do not want to use cones. If the stock feet have a higher profile than the soft footers then they will need to be removed, if not, then just leave them on and place the footers next to the stock feet though not touching them. The stock feet of my CAL were higher than the Pods so I just rested the CAL on a sheet of MDF (with the Pods underneath) and left the stock feet on the player. Lot's of ways to do it if you are not going to use cones as well at the start and it's kind of fun to listen as the sandwich grows.

Hi Dan: I used soft footers (Vibrapods) between the MDF (shelf) and the Maple platform and then brass cones between the Maple and the CD player. So, from bottom to top it was: MDF/Pods/Maple/cones/player. Red Kiwi has been having good results with the EAR soft footers which I would also like to try out under the Maple. Since that setup I killed my MDF shelf and have the player resting on my cabinet itself which is constructed out of Persimmon wood. Both setups sound pretty much the same to me so I guess that the soft footers are doing their job well. Different soft footers will sound, well, different. The Vibrapods are $24.00 for a set of four and the E.A.R's are $3.25 each from what I can discern from the Parts Connection catalog on line. If you happen to have a Maple cutting board handy (even if it is only 3/4") you can get started for not a lot of money. I am using the least expensive Mapleshade brass cones which are $38.00 for a set of three and their most expensive set of cones is $110.00 per set. I will eventually try the $110.00 set (which another member is having good results with) on my player. I am using the cones on my DAC right now as well. Even if you only start out with soft footers and a platform on which your player rests on it's stock feet you will still here a nice improvement in the sound much like as if you have upgraded your player, which you have just done in a way. The first time I placed my player on a Vibrapod/MDF platform, I was hooked and the subsituted Maple platform sounded even better prior to adding cones to the equation.

Thanks DeKay. Good to know that I will not have to replace my MDF with other material. So did you spike the maple directly into the MDF or did you use a plate of some kind to keep the spikes from embedding themselves? - Dan

Dan: I have tried what you are describing with Pods (instead of EAR's) and Maple on top of MDF and it worked fine. You have to start somewhere, and work yourself up, which is in your case an MDF shelf.

Hi Red: No I have been unable to print their catalog and order form (I keep getting an error message) and cannot read the download on my screen even using an electronic magnifier. I need to just order by phone and have been too lazy to do so. I can make out $3.25 on the page and assume that these are the ones that you are using. I would need a set of "light weight" ones for the DAC and a couple sets of 20+ pounders so that I can try them out on my player and speakers. I have pretty much decided not to "top weight" my components as I do not like the decrease in harmonics that I seem to get with this approach, though I am curious about the Mapleshade method of applying the weight through tiny contact areas and may try this out with some DIY stuff before I say never to this method. I had thought of using BB's under flat weights for this test. I will pick them up (the EAR's) soon though. Right now I have too many changes taking place (new outlets, new tubes and a PC on the way) to evaluate isolation devices. I was just talking to DanVet and mentioned something (that I have never noted in the forum) that might interest some. When I test isolation components I switch them out while music is playing (just be careful and keep the player level if that is what you are working on - I would not attempt this with a turntable, LOL) and am able to hear the changes that take place right away. I use two narrow pieces of wood (along the sides of the component) to elevate it while I am changing the sandwich underneath. I also use this method when I am clearing/isolating cables and PC's and can hear the music "clear up" as I fuss with the cables. I prefer to do this on my own with the support blocks so that the equipment is not dropped (I then have full control over the situation). This would not of course work in cases such as the Nuance shelving in which it takes many days to settle but seems to work fine and expedite the process with footers, cones and more stable platforms such as Maple. The pods that I use have already been well squished and I would probably want to do the same to the E.A.R. feet before using this method. I can usually evaluate changes (to my satisfaction) within a half hour or so by playing different source material, I don't use special "test" CD's.

Redkiwi, Sorry I am confused again. I think this thread is great. Please clarify this for me... You said don't MDF if you can at all help it, but if you must use MDF (as I have to in my MGD JustaRacks) then use hard damped cones between the MDF and the component? Or assuming that the MDF shelf is still in the system, can you put a shelf like the Neuance on top of the MDF separate them (Neuance shelf and MDF shelf) by hard damped cones and then use the e-a-r feet between the Nuance shelf and the component? Is this close to what you have found? - Dan

Dekay, did you ever try the E-A-R feet? They work in the context of my overall approach to isolation, and several of my audio mates locally concur, but am very interested in what you thought.

Hi Equa. I don't agree with using thick MDF shelves, but if you do then use spikes between rack and shelf, and try out some of the hard but damped cones like Walker and BDR. This will stop the MDF creating a lot of muddiness. Better still use a very light and rigid shelf like Torlyte or Neuance and use the E-A-R feet (remembering to match the size to the weight). Another good option is Maple Butchers Block - much better than thick MDF if you don't like the light and rigid approach. I am sure that there are other ways to go than I have outlined, and they may be better, but hope this helps with one set of answers to your questions.

Equa: This is the shortest (by far) thread that I have seen on the subject. Search for the "shelf material(s)" thread and their will be more info.

This thread has gotten large and complicated - what have I started?! As a new "audiophile", I remain somehow confounded. I am building a heavy welded steel rack, with thick MDF shelves, and I still need (3) (simple?)answers, ie:
Rack to Wood Floor: Hard Spikes or Soft Pads
Rack to Shelves: Fasten Tight or Isolate w/ Pads
Component to Shelves: Isolate w/ Soft Pads/Cones - appears to be correct.?
Thanks again for all your help!

To anyone trying out the Neuance... When you first put it in place it will sound warm and woolly, then it will gradually sharpen up but you will find there is a problem in the upper mids, then it will gradually improve and become fast, neutral and detailed. This takes up to a week (maybe more to fully come right). This means that experimenting can be a problem. That is, if you try and change footers etc to fix the early sound problems you will be driven crazy. Particularly as the sound will go through a similar process again until your last change has settled in. I have never experienced this with a shelf before. The mistake I kept making was trying to ameliorate the upper-midrange resonance you get after two or three days. I have found this out the hard way. I suggest that the best way to use the Neuance is to support it with a welded steel rack, firmly spiked to the floor and with spikes supporting the Neuance - and then leave it for a week, regardless of what it sounds like during that time. When it has settled in you will find notes start and stop very quickly. It took me a while to figure out whether this was right or wrong. My previous setup and the Maple Butchers Block romanticised the sound much more, but the Neuance was more revealing of the different character of disks and was just a whole lot less noisy. In the end I concluded that my system with the Neuance was much closer to what I hear at live events.

Hi Jaybird, I can say between the surefeet and the triplepoints that the triplepoints do sound better. I was surprised at how much better. The surefeet sounded warmer, less articulate and not as precise as the triplepoints. The soundfield is broader, deeper with better separation with the triplepoints. When you get yours, be sure all 3 points are touching the bottom of whatever you will be using them with. It can make a huge difference in sound depending on what the triplepoints are going into. Experiment and try to have fun. It does become a bit of a job after time.

Then, you might try the poor-man's triplepoints! (There might be a better substitute than double-sided tape, but the tape's not bad. Gives a pleasant golden sheen to the sound -- just BS-ing of course.) It's easy to see, intellectually at least, why the triplepoints, with their guaranteed positive contact and the greatly increased pressure at the small areas of contact, would accomplish better energy transfer.

Jayboard: I checked both sets and they are OK. The only problem is that the sheet metal on the bottom of the CAL player is not completely flat. The cones however when tested on a sheet of glass with a little moisture between are very close. Thanks Brulee, we will wait then for the wild ride.

Try the cones under a speaker, Dekay? Heck, why not. When my new order comes in from Mapleshade, I'll try it. I was really only looking for a cone that would sound a little faster in my turntable setup (and will try the Ultimate triplepoints there), but my CDP asked for a tryout, too, so why stop there? I put three cones under my cereal bowl this morning, and damned if the oats didn’t taste a little more like oats, and the corn a little more like corn. Seemed to stay crunchier, too. ...... Mapleshade is aware that every once in a while their cones have the tiny nib on top that wasn’t completely machined off. From my experience, you’d hear it if you had it. ...... My mind is on feet these days, so Brulee and anyone else, any further notes on feet comparisons are welcome.

Thank-you Redkiwi, as always a thoughtful responce. I'm excited to try out the Neuance, and I'll keep you informed.

Thanks Redkiwi, I know you have put a lot of work in this and I am sure everyone appreciates your efforts. I know I do. Hi Dekay, at least you have a valid excuse. I do stuff like that all the time. You are an hour south of me and I do look foward getting togeather with you. I have a few toys we can play with. Should be fun.

I was only able to try a BDR "shelf" overnight and would hate to pass judgement on such a short acquaintance. Clearly you not only like it but have far more experience with it. For the little that it is worth, I found it to slow things a little and to have the effect of lightening the sound. I am struggling to describe what I only vaguely remember hearing, but there was something going on that tilted the sound upwards, that did not so much result in brightness, but removed (what I feel was) natural body and weight from the middle of the mid-range down. I also felt it was unnaturally smooth in the treble. I only really tried it with my transport and with BDR cones too (which I now think was not a good idea), with a very brief flirtation with my DAC late at night. I would have liked a lot more time with it but felt that the approach was not quite what I was looking for. I would guess you will find the Neuance faster, more neutral and more naturally detailed, with a more ruthlessly revealing and less smooth upper mids and treble. But please, take this with a few pinches of salt. I will be very interested to hear your thoughts on the Neuance, and will let you know within the next few weeks how to get the best from it (in the context of my system, that is).

Redkiwi, I ordered the Neuance and it will be up to 4 weeks befor it's here. I was wondering if you ever tried "the shelf" from Black Diamond Racing. I have one under my amp and love it, but under my SACD or pre-amp it really wasn't successful. I'm planning on the Neuance with the SACD, and just wondering if you had experience with "the shelf"

Hi Brulee. I am trying to shut up on this topic at the moment because I still have a lot of experimentation to do before I can be happy I know what these shelves really sound like. I find the Maple Butchers Block is pretty much as you describe Brulee. There is plenty of life and soundstage size with the Maple, but there is some lack of leading edge or pace. In the end I believe the Neuance is more promising, but I am yet to be certain about the Neuance. There are two reasons for this. The first is that I really want to try it out in a few systems. My main system has at least one unusual characteristic in that the floor is very hard. This means the termination between rack and floor can be very influential on the sound and I get quite different results in my other system where the floor is wooden. The other issue is to do with the Neuance itself. When you use a Neuance shelf for the first time the sound is quite warm and woolly, but the sound clears up after a few days. I have repeated this experiment just to make sure I am not crazy, but it seems that the exterior of the shelf will have some compliance when you first put pressure on it, but that it settles after a period and becomes a much firmer support. The sound seems to change for up to a few days and so experiments with it can take rather a long time. With some of my earlier attempts with the Neuance I had some problem with upper mid-range resonance. I am trying now to understand whether this is a fault of the Neuance or a fault elsewhere (which, as we speak, appears to be so - ie. not the Neuance's fault). But there is no doubt that the Neuance is way ahead of anything else I have heard in terms of transparency, extension, dynamics and detail. The sound is stunningly open throughout the spectrum, but perhaps the most striking feature is that treble detail is just absolutely fabulous, with no hint of smearing.

Brulee: My memory as well as my old emails are wiped out, but I am pretty sure that you are just an hour North of me. If so, let's wait until we can hang or take a road trip together. If my memory is wrong please let me know and I would then like to check out the Maple via mail per your kind offer and will cover the shipping both ways. If I have confused you with someone else (perhaps Gthirteen) then I apoligize to both parties for my lapse. I was pretty fogged out a while back from some medication, to the point of making coffe one morning with dried cat food instead of ground coffee:-)

Hi Dekay, I am using 2 1/4 inch thick maple butcherblock that I got from McMaster & Carr. I found this thanks to a post left by Albertporter (thanks Albertporter) on another thread. It came 6'x 30"x 2 1/4". I was able to get 8 15x18 boards. I have one I can let you borrow for a few weeks if you like. I could ship it out to you tomorrow so you could have it for the weekend.

PS: Everything has also changed with the new 300b amp and I may have to start from scratch again and try everthing that I have already done all over. The first thing that I have noticed is that I can tilt the HF's up much more without is bugging me. I should probably wait until I re-tube before I run the gauntlet again. The only MDF that I am using right now is under the amp itself.

Brulee: How thick is your Maple platform and is it butcherblock or of a simpler vertical glue/lam design. I am still using 3/4" Maple (not butcherblock). I do not want to cut up my 5' 2 1/2" thick Maple butcherblock yet as I may want to use it in another cabinet one of these days if and when I can relocate the gear. I picked it up for nothing many years ago but the replacement cost of this "slab" is quite high. I have also cleared another 6" of vertical space (for the time being) in my cabinet (the new tube amp sets on top now) and would like to try the Isoblocks (they are only $24.00 which is the same as Vibrapods). My wife finally noticed the cones, or the use of them as they were in the shadows (when the sliding doors were removed from the cabinet) and asked "why is the CD player floating in air?"

Hi all, I have been getting very good results with the Mapleshade triplepoints under my equipment with the triplepoint cones sitting on maple butcherblock. I am also using Mapleshades isoblocks under the maple which sounds better than using there cones. I have been experimenting with different stuff on top of gear and found the Mapleshade heavy hats (brass weights) work much better than VPI brick, lead weights, or lead shot. I found out that you can change the sound with too much weight or too little. Fine tune until desired results or go insane trying. It seems there might not be a cure all as much as finding a sound that will suit you. Dekay, when I tried using cones going into MDF it was lifless in comparison to maple. I feel I have a good handle on the Triplepoints and will try other feet (materials) to see what sound changes occur. Redkiwi, do you think the neuance is better sounding than maple? I feel the maple slightly softens the leading edge but still maintains energy, life or what ever you want to call it.

Plsl, after playing some more and reading what arrangement sounds good to you, I reckon you should try some Maple Butchers Block.

Darn it Jayboard, now I am going to have to pull the Mapleshade cones and check their level. When I tried the Racing cones between my player and an MDF platform resting on Vibrapods I found the sound to be kind of "etched" for lack of a better word. However, since then I have discovered that they make different models and wonder if I may have used the wrong one for my application. I borrowed a set of three for the test but am not certain what number they were and have not yet asked the friend that loaned them to me. I have heard good things about them from others and would like to give them a second try (the other model) before dismissing them. I happen to have some brass finish nuts (the ones used to affix glass ceiling light fixtures) oddly enough. LOL. If you get a chance try the Mapleshade cones under one of your speakers. I just messed around with my wiring and wall outlets and am taking a break from tweaking until the sound settles down.

Wow... As a reatively new "audiophile", I am impressed. I think I am beginning to see why some people spend a lifetime "tweaking".

Dekay, or anyone, can you offer any comparison between the Mapleshade and BDRacing cones that you used? I'm looking for a cone... for a different application -- between a Rega Planar 3 and a sandbox... but any comparative info still would be interesting. BTW, at first I was disappointed in the Mapleshade Surefeet -- got new detail and better defined bass but also some aggressive highs and too-light bass. Then I discovered the cones weren't perfectly flat on top; they had a tiny nub dead center that prevented uniform contact. To bypass the nub, I got some tiny brass cap nuts (dome shaped) and stuck them on the flat top with double-sided tape, thus creating a poor-man's version of Mapleshade's triple-point cone. Now, I am favorably impressed with the Surefeet (tried under turntable and CD player). I will exchange this set for a good set and may try a set of the heavyweight triplepoints as well, but the capnuts may still figure into the mix.

Thanks. I also have a Theta Data III. The cabinet is quite susceptible to air induced vibration at mid bass frequencies. I have mine on a Zoethicus stand which sits on an oak plank base seperated from the floor by air bladders. On the stand the Data III currently sits on a lead shot tray and is mass loaded across the entire top (except the vents) with a thin bag of lead shot. I like the sound and by lightly touching the cabinet before and after it is quite clear that the cabinet vibrations are gone, However, I'm always looking for what might be a better alternative.

Plsl, I am still trying things, but like something light and rigid, not just because that is what I am trying right now, but discovered some time ago that the Theta worked better that way. I would want to keep trying things for another week or so before I am too definitive but so far the Neuance shelf with E-A-R large feet in between component and shelf sound pretty good. I will also be trying oil filled bladders (but air bladders were not good) and Maple Butchers Block. None of these are shabby, but will take a bit more time to try out fully. The time consuming part is of course that you can only ever listen to the whole system, not parts of it, and different components may benefit from different supports.

Thanks for the follow-up Redkiwi. I know others that use a similar approach as to what you do and they too are quite satisfied with it. While i have never ventured down that path myself, i might end up trying it soon enough. In terms of using the sandbags, my main use of them is primarily for lightweight items like tuners, some cd players, etc.. or components with thin and flimsy lids that tend to resonate , ring or rattle. I think that you get the basic idea. As far as damping components internally goes, does anyone know who the first company was to do this on a production model ? I already know the answer but am curious to see if anyone else does. Any takers ? If so, please be as specific as possible : ) Sean >

To Redkiwi. If I recall correctly you have a Theta Data III. If so, what isolation approach do you use?

Hi Sean. My view is that mass loading of components has pluses and minuses. I hold to my view that mass in general is a bad thing (for reasons both you and I have referred to above), but is a necessary evil in the pursuit of rigidity and damping. So therefore you are best to only add mass when it has a significant pay-off in terms of damping or rigidity. Mass-loading a component does nothing for rigidity, so the benefits can only come in terms of damping. Arguably, adding a ziplock bag of sand on top of a component is doing three things; it is damping the ringing of the top plate (and to a degree the whole structure) with a substance that is unlikely to feed energy back into the top plate (this should be good); the extra weight will also lower the frequency that the top plate will vibrate at and will cause it to release its energy a little more slowly (this is not so good but is part of the inevitable consequences of damping); the added weight, as you ptu it, "will increase the energy transfer from the rack into the component". Personally I don't think adding weight in this way is the best way to go. It can appear to have beneficial consequences in terms of smoothing out peakiness and can appear to add bass weight (when all it is really doing is smearing the bass). But I shouldn't be so dismissive - it is just that with my overall strategy to the vibration issue, mass loading does not have benefits. If I followed a different overall strategy, such as the "massive" structure approach some take, or the clamp-rack approach that others take then mass loading may make more sense. Using my approach of light, rigid and damped, I believe I can get the good parts of mass loading without the bad parts by using another strategy. Essentially I modify the component by damping it - usually internally. While this is too intrusive an approach for many people, I just see it as good sense when most components are just not put together well. If you have a chance, have a look at a Sonic Frontiers component one day - while I don't particularly like their electronics, the boxes they put them in are brilliant. Much thicker steel panels than you usually find, able to be very securely fastened, judicious use of panel damping and good use of damping/isolation of the electronics from the box. It is poor attention to these details that I reckon using sandbags can ameliorate, but at too high a cost.

Hi Equa: I also play the isolation game and divide it into two categories as follows. The first step is to isolate the platform or shelf (from external vibration) that is beneath the component. I use Vibrapods for this, Redkiwi is currently using E.A.R. feet and there are many other choices though I do not prefer cones for this purpose. The second step is to "draw" vibration away from the component itself. I use Maple shade cones for this right now and in the past experimented with a set of Racing cones. The first step makes a significant improvement, IMO and the second step takes it up another couple of notches (at least) and allows further fine tuning of the sound. My current set up (from top to bottom) is Persimmon (the cabinet itself)/Vibrapods/Maple shelf (not butcherblock)/Mapleshade Surefeet cones (their cheapest)/CAL player. My DAC is Persimmon/Mapleshade cones/Bel Canto DAC (no soft footers on this set up as of yet, but I will try them soon). I also just tried Persimmon/four pieces of mousepad/MDF/stock soft feet on my Audion amp and this sounded much better than the amp resting on the Persimmon alone and I will experiment with footers other than "mouse pad" and would like to try the E.A.R. feet that Redkiwi mentions. I started out by just isolating am MDF platform for the player with Vibrapods (the player rested on the MDF on its stock feet) and went from there to using various other materials, so the initial investment can be as little as $25.00 to get started. I recommend using both systems from step one and step two for the best results on digital front ends. I sometimes find the use of cones to be impractical (on speakers and delicate items such as tube amps) because I live in the sunny land of earthquakes and do not want to come home to find that my speakers or amp have crashed to the floor which rests way below. The cones did sound wonderful placed between the stands and my mini monitors (the same went for when I tried them on the amp) but I am not willing to take that risk as I do not have a closet full of spares at this time. The same goes for children, pets and the uninitiated around cone mounted gear, earthquakes aside. PS: Just read the first few sentences of this post as they contain most of the useable information:-)

Sean, just a thanks for your follow-up. Jayson

Red, just to clarify something that i've been wondering, have you ever played with "mass loading" any of the equipment ALONG with the various types of isolation / damping type devices ? By this, i mean applying weight to the top of the component ( i.e. sandbags, VPI bricks, etc...) in conjunction with the other tweaks ? My experience is that "lifting" the component higher up of the shelf via cones and "levitating it in air" in effect makes the entire unit prone to ringing and airborne vibrations. This problem does need to be addressed, as it becomes more apparent as volume level is increased. The key to making this work is to find the right amount of weight to damp the cabinet vibrations without adding TOO much mass. Going too heavy will increase the energy transfer from the rack into the component, minimizing the isolation effect of the cones. In order to do this, one must have the weight properly spread out and not concentrated in any one specific area. Freezer sized "zip-loc" type storage type bags filled loosely with a layer of sand can work wonders. Of course, you must pay special attention to ventilation and sources of heat, as blocking off air flow can result in not only a mess with the melting plastic, but also "meltdown" of the equipment in question. Just wondering what your thoughts and experience are on something like this. Sean >

Not at all Sean, instead I am a bit embarrassed at your flattery. The general conclusions I have come to are not detailed enough to answer all of the questions you list - but nevertheless so far I believe: it is OK to use multiple structures sitting on top of each other if they are either firmly bolted together or have a point contact - ie spikes or cones; each structure should be light, rigid and damped; there should be no more than one item in the structure that is compliant (ie. non-rigid), that the best place for this compliance is between shelf and component, and that so far the best I have tried are the elastomer E-A-R feet, which have the most even-handed sound without smeering detail. The biggest problem is to achieve the requirement of light, rigid and damped. I believe that if you achieve this in just one place then the best place is in the shelf. All supporting structures under such a shelf can be just light and rigid. Light is important because it means little energy is stored and passed on through the chain - for this reason I think many heavy and damped shelves sound neutral, but smear detail (due to the slow release of too much energy). Rigid is important so that any energy is released as quickly as possible, and because otherwise you may end up with more than one compliant support, causing resonant nodes. Damped is important because if everything was just light and rigid it would ring (the peakiness I have referred to). But I reckon the idea of light and rigid, to make sure energy stored is minimised and released quickly, is in natural conflict with the concept of damping. By its nature damping tries to absorb energy and not return it later, but that is a difficult ideal to achieve in practise. It is in this trade-off that I feel there is as much art as science - finding the trade-off that does the least damage to the music. The reason why I like the items closest to the component to be damped or even compliant (in the case of the feet) is because the component needs to be both isolated from vibrations by the total structure, but also damped. I suspect I am just finding more ways to say what I have said before, but hope this clarifies. But this time I am explaining things in a way that (I hope) is related to Equa's question (isolation or absorbtion). My preference is for the focus to go heavily on isolation, but with a small amount of absorbtion close to the component. I don't like many of the absorbtion products (eg. sorbothane and bladders) because they release energy back into the structure slowly, thereby causing smearing and lack of focus and pace. Used on their own they may subjectively provide an improvement where isolation has not been dealt with well, but I don't think they are the best way to go.

To add to the above novel, i hope that Redkiwi (or anyone else) does not think that i was attacking him in any way or take anything personal. I have greatly enjoyed many of the posts that he has made on this subject and tend to agree with many of his findings thus far. I was simply commenting on some of the examples that he had referred to in his post and as such, he became an integral part of the response. No disrespect was meant to him, his views or anybody else that does not share my view on the subject being discussed. I hope that i did not come across the wrong way and that my comments will be seen in the correct light. Sean .

I'll try to address both Dan and Jay's questions here as briefly and simply as possible while touching upon Redkiwi's comments. In terms of the MGD rack, i had originally added large "fender washers" between the locking nuts on both the top and bottom of the shelves. Michael said that this was a big no-no, but the nuts seemed to be digging into the shelving material quite a bit and leaving "uglies". He told me that if this was happening that i had the nuts too tight. Tightening these down quite a bit was the only way that i could keep the rack from swaying or leaning to one side (my floor is not level). I was EXTREMELY meticulous as to having the rack level on all shelves and keeping it rigid made that a LOT easier. I have since taken to "playing" with the tightness of the top clamping nuts on each shelf. This has greatly affected the tonal characteristics of the bass, amount of air and ambience along with the overall "pace" of the system. It has also resulted in a rack that is slightly less stable due to less rigidity. That might be a lesson in itself. As to cones or coupling in general, i DO agree with Redkiwi's comments that cones that are securely mounted to a component and not just resting on top of them is more effective. The cones become an active part of the chassis when this is done. In effect, you no longer have an individual component and cones but a one piece chassis with better transfer characteristics. As to explaining the transfer function vs. surface area and coupling, i am not a mechanical engineer nor do i have any background in such. Most of my "deductions" were arrived at from a "logical" train of thought and experience. Reverse my "logic" in the article that Stereophile published. Instead of thinking about how the "arrows" were driven down into the shelf, see how easy it is to drive a nail into the wall with it pointing the wrong direction. There is OBVIOUSLY a major difference in how efficiently the energy is transferred depending on the shape and amount of contact area between the two mating components. Another KEY factor in this equation was brought up by the "Kiwimeister" in terms of the materials used. Redkiwi's comments about specific devices sounding "peaky" or having common sonic traits has to do with the overall transfer of energy between the entire component / shelf / rack / floor / room synthesis. There are obviously vast differences in densities and ranges of resonance in various woods, polymer's metals, etc... Which material works best where or how all of these will blend together is anybody's guess. After all, while we look at each component as an individual link in the chain, the system IS the WHOLE chain and sums everything as one. For those that have electronics background, think of a circuit with dozens of components in it. Even though each diode, resistor, capacitor, inductor, etc.. has specific characteristics, they can all be summed up as one big "MASTER" complex impedance as described in "Thevenin's theory". In our audio system, we could call it "the MASTER complex resonance". It's just a combination of all of the smaller resonances added and subtracted, etc... How to arrive at what sounds good to us is a pretty complex ordeal, just like the above described circuit. While i know that Redkiwi has spent a sizable amount of time investigating some of these specific areas, he may not have come to any "solid" conclusions. To make any real progress in this area would really require test instruments and extensive notes and documentation for various situations and installations. There are SO many variables involved in terms of different isolation / damping devices and designs along with materials for those AND the shelving that you would literally need a lifetime to document them all. It is hard to imagine that ANYONE knows the answer to ALL of the following questions: 1) Do you isolate component A or dampen it ? 2) Do you know which shape or style of isolater / damper works best ? 3) Do you know which material to use for the isolator / damper ? 4) Do you know the optimum place on the chassis of the component to place the isolation or damping device ? 5) Do you know what material, shape, size and weight to make the shelf that the component will be resting on ? 6) Do you know if the shelf / rack should be rigidly coupled to the floor or if it should be isolated ? Etc... This is the reason that so many tweaks exist. There are NO answers set in stone. It is all a matter of trial and error as to what works best, what works poorly and what doesn't work at all. While keeping a notebook on such things might be considered "anal", it might actually produce some very interesting results. I simply offered some of my thoughts / observations as to what i've encountered so far and Jonathan "ran" with it. Like the rest of you, i'm still guessing, learning and "playing it by ear" too : ) Sean > PS.... To all of the "non-tweakers", hope you had a good laugh : )

Thanks for your comments on my questions everyone!

Redwiki - Never mind. Just read your other string. Will try the EAR devices.

Redwiki - Based on yur research, what would you recommned instead of cones for equipment sitting on glass shelves? My tubed amps amd pre amp sit on glass-shelved Target amp stands. I tried BDR cones and they improved focus/accuracy vs. the crappy stock rubber feet, but I admit I've not done further experimentation.

I don't buy the mechanical diode idea as anything more than an analogy (and all analogies are inaccurate), and tend to agree with Mapleshade that for a cone to do its thing it would ideally have a point on both ends - hence the Mapleshade idea of three points on one end and one on the other. Conventional cones sound the best when the flat side is up against the surface that is vibrating least (the equipment), since the flat side does the worse job. Hence also why cones can sound better if they are bolted firmly to the bottom of the equipment. I reckon cones between component and shelf do their job because they release energy very quickly at the pointed end. This reduces smeering, but creates peakiness. The sonic differences between cones depend on hardness (speeds the release of energy), resonance/damping (determines the peakiness) and mass (slows the release of energy), but are also profoundly influenced by the shelf material that the pointed end rests on. The more the shelf material is like the cone material, the more you will hear the peakiness of the cone. In my opinion, cones are only good as an antidote to a shelf that has too little rigidity and too much mass (such as MDF). This is just my theory developed from my experience, no more than that, and I respect the fact that other theories presented here may be more accurate.

Sean, since you mention that your explanation of how cones do what they do was quoted at length by J Scull in Stereophile, can I ask for more explanation? No disrespect intended – for you are a sane poster whose views on AudiogoN I tend to pay attention to – but I did not find the S’phile quotation very enlightening. The diode metaphor of how cones pass vibrations one way has an obvious appeal to it, simply because cones look like arrows, but I’ve often wondered if there was a scientific explanation behind it. Your chain of thought about how cones work to drain vibrations in one direction and block vibrations in the other is quite logical and, as you say in your explanation, “it’s all quite simple.” However, in the end it all rests on the familiar proposition that cones pass vibrations one way – which, in my mind, you basically reasserted, rather than explained. ---------- Ideally, the contact area between a flat surface and the point of a cone that meets it is just that, a point. What difference does it make to vibrations on which “side” of the point there is flatness and on which side there is cone-ness? Again, the diode metaphor appeals in a visual way – vibrations get funneled through the cone in one direction but cannot squeeze into the point from a flat surface in the other direction; lower frequency (floor-borne) vibrations have more trouble than higher frequency (equipment) vibrations fitting through a small point – but I don’t assume that necessarily has any correlation to science. Is there any further explanation you can add for this proposition? ---------- BTW, this is a matter of intellectual curiousity, and I am not implying that I need to hear a scientific explanation before I believe that cones have an effect. Right now, I am comparing Mapleshade brass cones against the cones I currently have under my turntable, and there are differences to my ear. But, speaking of Mapleshade, that company sells higher-priced brass cones (Triplepoints) that have three “micro”-cones sticking up from the flat side of the cone. The cone is used point down, and the equipment rests on the points of the micro-cones rather than directly on the flat surface of the cone. The designer Pierre Sprey says that minimizing the contact between the equipment and the big brass cone improves the transfer of vibrations from equipment into the feet. Not that he gives a scientific explanation for this (though he might have one if I asked) ...just another example of differing points of view (no pun intended). -- Jayson

Not to get off topic, but Sean what tweaks did you make to your Justa-Rack. I have two of these and I found your comments very interesting. - Dan

Redkiwi makes some very valid "points" : ) My experience is that i have noticed EXTREME differences when changing racks and isolation devices. I had a "home-brew" all wood rack that i had everything dialed in on very nicely, but i added more components and needed a bigger rack. The way that i had built this rack did not lend itself to "adding on" any further shelving. I went to a Michael Green Designs Deluxe Just-A-Rack and it COMPLETELY changed the way that system sounds. It was SO obvious that i had to put a different amp into that system to "re-balance" it. Upon further consultation with Michael, it turns out that i had tightened the nuts down too tight on the shelves and this was causing the massive (read as "less than good") changes that i had noticed. I am currently in the process of "fine tuning" the characteristics of the rack and it is making a VERY noticeable difference in bass output and tonality, timbre of instruments, attack and decay characteristics, etc... Quite honestly, i would have never believed that something like this could have made SUCH a noticeable difference in a system. As others here have mentioned, this is more of a "black art" involving a LOT of trial and error. While some of this stuff can be understood logically, as to what works best and where at in the system is strictly guesswork and experimentation. Not to toot my own horn, but i covered some of the logistics of why cones couple / uncouple in the February issue of Stereophile in Jonathan Skull's "Fine Tune's" column. He thought that i had hit on something with my original post on that subject and thought it might be worthwhile to share it with others that might not have been able to see it on the web. As such, some of it was slightly altered for publication but the "guts" of the post remained intact. The bottom line is that one MUST be VERY familiar with the system in the first place before subtle changes can be easily detected. Until you have achieved a very good foundation that your basically happy with, doing small "tweaks" to fine tune it might end up taking you in the wrong direction. Hope this helps. Sean >

equa: i was hoping rekiwi would respond first to your thread query. he's shared with us in erudite posts his experiences testing "footers/shelf material." i recommend you review the thread of that name. i just wanted to comment on your observation that this hobby is informed with "subjectivity and contradictuions." you are right, of course, but these characteristics are what give it life and, indeed, form the basis for sites like this one. as redkiwi attests: there are no "simple answers" to the paradoxes you'll encounter if you get deeper into the hifi world. don't let this bother you or you'll go a little nuts. sit back, ponder and then enjoy the music as your journey lengthens. good hunting. -kelly

If there is an answer, I haven't found one. You mention soft pads isolating a CD player - if only.. All they do is change the resonance to a lower frequency - whether this is better or worse is a matter of taste. Arguably a soft pad allows the vibration to last longer, whereas a cone causes the energy to be released quickly. The former does damage to the perceived rhythm and timing of the music, whereas the latter can induce peakiness in the mid-band. Currently I prefer using E-A-R elastomer feet which are nothing like as soft as sorbothane (which sounds ghastly), and nothing like as hard as any cones. Whether or not shelves should be supported by spikes or soft footers depends on the shelf material. Spikes on a hard shelf like glass etc tend to sound awful, but better with soft shelves like MDF. The rack itself and damping of the shelf are other factors. Alas, simple answers escape me despite my efforts to date.