I recently discovered the benefits of isolation. Don't know how many of you are familiar with
Barry Diament's
recommendations for his hip joints. The recommendation for the economical DIY set up worked well for my stereo; (lightly inflated bike innertubes, wooden egg holders supporting stainless steel balls).
A month ago I bought Isoacoustic Oreo's. 3 per component (weight appropriate) and was very impressed...at first. After several days of settling my music sounded dull and lifeless. I reread
the optimal weight recommendations, re-calibrated weight limits with temporary improvements. To my disappointment I realized the Oreo's could only be compressed (especially after the suction seal was formed between them and the component or platform the component sat on). Sure they rocked in all directions, but they didn't glide in all directions. Only horizontal isolation was taking place so I coupled the Oreo's with Barry's economic hip joints which has greatly improved the SQ. I'm loving it but I still feel there's room for improvement. Mainly because I own the Hfiman HE-6SE HP's and I run them through my power amp's speaker taps. So I want Barry's upgraded hip joints under my amp. I'm interested in Ingress Audio's vibration isolation rollerblocks.
http://www.ingress-engineering.ca/products-and-services.php I've looked up info about their level 2's and 3's but specifics on their differences aren't given. I know Barry says the blocks should be machined smooth to a certain degree. I left a message with Ingress, but I'm impatient and wondering if perhaps the level 2's aren't as smooth as the 3's. The smoother, the greater the improvements.
My question is does anyone know the differences between their Level 2 and Level 3 rollerblocks?
@mewsickbuff, I can help ya’ll. Not that I want the credit, but it may have been I who brought Ingress Engineering to the attention of Audiogoners a few years back. I had read Barry Diament’s writings on the subject of isolation, and found his argument persuasive. So I bought myself a couple of sets of the Symposium Acoustics’ Roller Block Jr’s. They are a fine product (as are all of SA’s), but I couldn’t help noticing that the design of the Jr. was quite a bit different than Barry’s Hip Joint design. In contrast, the much higher priced "original" Roller Block did adhere to Barry’s idea of a single cup and ball bearing.
So I did some more investigating, and came upon a forum upon which Barry’s ideas were being discussed. I was not alone in my quest for perfection! A group of DIY’ers had come to the attention of Michael of Ingress Engineering. He was making what was essentially a knock-off of the Symposium Jr. (no offence Michael ;-), and selling his version for about half the price of the Symposium. The only difference I could see was the Ingress wasn’t anodized black, being just natural aluminum. The Ingress was about 1.5" in diameter to the Symposium’s 1.875", no big deal. The diameter of the bowl appeared to be identical, so I ordered some. Sure enough, the two were essentially the same. They were both made of 6061 aluminum, and polished smooth. Since the Ingress is non-anodized, you can see your reflection in the bowl!
But being perfectionists, forum members pointed out to Michael that Barry’s Hip Joint design called for a much larger bowl to be carved into the cup. The larger the bowl, the shallower the incline the ball bearing must climb when confronted with vibration (the basic idea of roller bearing isolation), and the lower the resonant frequency and greater isolation does the roller bearing provide. Barry’s design also was just a single cup with a ball bearing, not the cup-over-a-cup design of both the Symposium Jr. and the Ingress. To his credit, Michael went to work and created a second model, one just as Barry Diament had described and machined locally for himself.
The second model was a single cup, with a bowl of much larger diameter carved into the cup. The cup was machined out of the harder 7075 aluminum, and polished to a finer degree. Now we’re talkin’! I got myself a set of those, and man are they great! At the time Michael was selling the new model for just a little more than the original; only one cup cut down on cost, but the 7075 aluminum cost more, as does the time and effort expended polishing the bowl to a smoother, more friction-free finish.
Now having all the roller bearings I needed for my system, I stopped paying attention. Your post lead me back to the Ingress Engineering website, and I see Michael is currently offering two models (plus a larger one for loudspeakers), the improved one now called Mk.2, an even newer one MK.3. Both are single cup of the same size, both machined out of 7075 aluminum, and both have the same size bowl. The cheaper one is anodized black, so I’m assuming the pricier one has been polished smoother, but that’s just a guess. I have no apprehension in recommending either, or both! Buy a set of each, and compare them for yourself. You may end up with the pricier one under your source component, the cheaper under your pre-amp.
I'll beat Geoff Kait to the punch by pointing out that the roller bearing provides isolation in all planes but the vertical. In the vertical, it acts a coupler, not an isolator. To get isolation in that plane, you must look elsewhere. Geoff just happens to sell cute little springs which will do that for you ;-).
I bought some Ingress Audio V3 which I’m told are just a bit taller than the V2’s from a dealer close to me and use them under several components and just find them superb. I had been using the Symposium Jr’s but find these actually have a more open sound. Found out about them from a dealer I was visiting when saw them underneath some of his gear. With a small discount they are like 50% of the Symposium which I like but again like these even better. YMMV
Great posts above, especially @bdp24 ’s which covers it all.
I’ve been using the Level 3s (v1 and v2) under all of my components: from the front-front end of my computer audio gear through to my DAC.
I originally ordered the Level 3s and Level 2s (both version 1s) for comparative purposes and it was clear that the Level 3s were the way to go.
BTW, I’m using my original sets of Level 2s under my linear power supplies, a passive power conditioner, etc. HOWEVER, the current Level 2s look like the original Level 3s and are likely far superior to the original 2s.
I still recommend going with the current version of Level 3s.
There are many ways to skin a cat. I use those heavy one inch high glass candle holders for the base and either Super Balls or some appropriately sized ball made of glass, maybe a glass marble, or other very hard material for the balls. Super Balls are 1” diameter type sold in bubble gum machines. I Even if the surface of the base is not concave roller bearings will work for the horizontal plane. Hardness and smoothness of surfaces, I.e. low friction, are the critical factors. The best isolation is when there is great ease of motion. By the way cryo’d, heat tempered high-carbon steel is much harder than the best aluminum. Like my springs.
Thanks a lot everyone for your input. I've ordered 4 sets of the level 3's.
Barry said, "In fact, outside of digital gear, they may make the
largest difference when placed under speakers. When I first tried them
under my Magnepans I said that by comparison, having the speakers on the
floor was to have
them “bound and gagged.”
Which components did you guys isolate 1st, 2nd, etc.?
The reason vibration isolation is important is that low frequency vibration and forces related to that vibration affects the audio signal, including but not limited to the wiring in the wall, the wall outlets, the wall plates and the wall itself, wire in cables and power cords, internal wiring and electronic elements in the components and speakers. The audio signal itself is not (rpt not) a vibration per se or at least it SHOULD NOT BE but is affected by forces F of external vibration. Like magnetic field lines on a magnet are affected by rapidly moving the magnet manually.
The entire building is subjected to continuous seismic waves that are produced by many things including Earth crust motion, wave action on shore lines, trucks, buses, subways, cars, construction, footfall, wind. The entire building is forced to move in many directions. Seismic waves have six directions of motion, including three rotational directions. The horizontal plane x-z represents the other two directions 🔛, vertical y is the sixth direction 🔝. The three rotational directions are around the x, y and z axes.
The analogy to seismic waves and its influence on a building and everything inside the building is a boat ⛵️on the ocean when a waves in one direction passes under it. The boat moves vertically, sideways and also rotates back and forth as the wave passes under it. Waves in other directions affect the boat similarly but the boat moves in different directions according to the direction of the other waves. In order to reduce or eliminate forces F that seismic waves produce on the audio signal the entire audio system should be isolated, decoupled from the building. An object will remain at rest unless acted on by an external force. I’m disregarding acoustic waves in the room for this part of the explanation.
Roller bearings are interesting because they are capable of isolating the component in several directions of motion, low in cost, depending on how the roller bearings are designed. The most simple design is a cup with a flat bottom that has small diameter base so the ball can not move very far. Three of these roller bearing assemblies will provide good isolation in the horizontal plane and in the twist rotational direction around the vertical y axis. If the cup is concave the component can be isolated against forces in the other two rotational directions. The roller bearings are not effective in the vertical direction, well, perhaps a bit, never say never. The vertical direction can be easily handled by springs, very effective in the vertical.
Materials for the cup and bearing should be chosen with the goal of keeping friction very low, I.e., smooth very hard surfaces.
I's still waiting for the same responses I got when I brought up Ingress Audio on another thread some time ago. A couple of posters claimed whatever sat on the bearings would roll right off and couldn't believe it would work.
@ nonoise, for any statement made, there will be critics AND supporters. Music and the hobby of trying to make the SQ the best we can, with the means we have, is a SUBJECTIVE experience. These forums introduce and educate in areas we may never have thought about. A while back, I sat my husband down to listen to Tchaikovsky's 1812 Overture on my stereo. I could hear the highest notes of the triangle (or whatever instrument it was) but he couldn't. He can hear the triangle when our grand daughters ring it at our house. I found that interesting (and summed it up to the recorded triangle being too soft-lower db). I wish naysayers who post on forums would TRY before they reject (or keep silent) and admit that if they can't hear something doesn't mean nobody else can either. I'll sit my husband down for a re-listen to the 1812 Overture after I get the Ingress roller blocks installed and see what happens :)
I also have a PS Audio P5 power plant. Would anyone bother to put rollers under it? What about a turntable? I plan to get rollers for the speakers at a later time.
I also have a PS Audio P5 power plant. Would anyone bother to put rollers under it?
As I indicated in a previous post, I do use the RollerBlocks with Power Supplies / Conditioners. I've used the Level 3s with my SR PowerCell 12SE with good results.
FYI, I use a combination of four types of footers for my components, and since I am short a set, I'm using the SR MIG 2.0 footers with the PowerCell (at present).
What about a turntable
I do not have analog components, therefore cannot comment directly.
Like I said, (I) read these forums to learn. So what’s the answer @geoffkait? I’ll take a stab, increases wow, hum and/or flutter? (shrug). Enlighten me :)@elizabeth dirt cheap is ALWAYS welcome!
Geoff's excellent post has refreshed my memory. The concept of the roller bearing is a compromise between maximum isolation capabilities, and practical considerations. A set of three ball bearings between two flat, very hard, very smooth surfaces would provide the maximum isolation possible. Those surfaces could be the bottom of the component to be isolated (or something harder and smoother than it, onto which the component is placed---no rubber feet; put something with no compliance between the component bottom and the surface. Barry Diament recommends ceramic tiles, available for pennies at home stores) and another flat, hard, smooth surface (again, that could be a ceramic tile). But that would make possible the component sliding right off the rack or shelf it is sitting on.
For practical considerations, a pair of bowl-shaped structures are used in place of the flat ones; the bowl of course makes the component sliding off the ball bearings impossible. Now, the shallower the incline in the bowl, the better the isolation. When the ball bearings are presented with vibrations, they move microscopically, being forced to climb the incline of the bowl. The bowls' incline thwarting the movement of the ball bearings creates damping, a thing very different from isolation. So, the shallower the bowl, the gentler the incline, and the greater the isolation. That's why the larger bowl carved into the Ingress cups makes them superior in design to the Symposium.
The original Symposium Roller Block used cups on only the bottom, with the ball bearing in each of the three cups contacting the flat surface of the component to be isolated (Symposium makes little stainless steel plates for use under components, for the ball bearing to slide across). The Roller Block Jr. (and the original Ingress) used a cup on both the bottom and top, the ball bearing keeping them apart from one another. Barry's Hip Joint design called for a bowl on only the bottom, for maximum isolation. A cup on the top does, however, provide insurance against the component sliding of the bottom cup. If you want to play it safe, go with the double-bowl design.
The degree of hardness and smoothness of the bowl also effects its' isolation capabilities, the harder and smoother the better. That's why the 7075 aluminum of the Ingress V.2 and V.3 is superior to those made of the softer 6061. The V.2 and 3 all also polished with finer grit than other bearings.
As for cost, the bearings are sold in sets of three. Those sets are far cheaper than even one footer offered by other companies making isolation products. I agree with @rsf507, they ARE dirt cheap!
Heck, the Ingress Level 2 V2 is $95 CAD for a set of three cups and ball bearings. It is superior to the twice-as-much Symposium Roller Block Jr., and WAY cheaper than even a single Stillpoints foot.
Geoff, I’m going to guess the spinning platter of turntables is the argument to be made against employing roller bearings under them. CD/SACD players also have spinning platters, but of much less moving mass.
Stock interconnects, power cables, power cords, and fuses work "pretty good", yet that doesn't stop audiophiles from spending far more on them than would the cost of installing a set of roller bearings under every component in their system. I haven't tried a set with my Townshend Rock turntable, as I have a set of Seismic Pods under it. They provide isolation in even the vertical plane, the one limitation/failing of roller bearings.
So true @uberwaltz. For not much $, one can substitute harder, smoother tungsten carbide ball bearings for the stock steel balls. Symposium charges a small fortune for them, but they are available from ball bearing vendors for far cheaper.
By the way, whether or not anyone thinks the original Ingress was a "knock-off" of the Symposium Roller Block Jr., Symposium was in 1997 granted a patent for the "double-stack" design used in both bearings.
If the base of the roller bearing assembly is flat there can be only rotational isolation in the twist direction. 🕺🏻 Plus isolation in the horizontal x-z plane. You lose the isolation in the roll and rock directions. It is the rotational seismic forces that try to rotate the building and everything inside. If the base is concave the component is isolated in those two rotational directions. The smoother and harder the surfaces of the bass and base the easier the component will move when acted on by any external forces. Which means the whole roller bearing set up can easily get “stuck” when the balls roll to the edge of the base if the set up is not perfectly level and balanced. That condition limits the iso device’s isolation, since it cannot move further in that direction. Isolation effectiveness in a given direction is proportional to how easily the component can move in that direction.
Another advantage of a concave surface for the base is that when the component rotates slightly due to rotational forces, there is some degree of vertical isolation since the component moves up and down vertically 🔝 as it rocks and rolls, no? Up and down as it rotates around its centerline axis. Recall wave passing under boat analogy.
You can buy miniature 2” shallow ceramic bowls on line that might work very well and a glass marble of the appropriate size, one bowl on top and one on the bottom. Total cost for set of three roller bearing assemblies $30.
I's still waiting for the same responses I got when I brought up Ingress Audio on another thread some time ago. A couple of posters claimed whatever sat on the bearings would roll right off and couldn't believe it would work.
I believe I was one of those posters Nonoise. But it was not that I claimed they would roll right off , more I was having trouble in my mind seeing just what there was that would STOP the amp rolling right off very easily.
But at $70 I was willing to give it a try and nope it did not move a mm once sat down on top of all three so mind put at rest.
I too was part the earlier Barry discussions (on CA) on his hipjoints and had many offline conversations with. He is without a doubt one of the most gracious and pleasant individuals I have come across and has shared a wealth of info. Being relatively new to this hobby, this topic goes back even earlier on other forums and I think he bowed out as some indiv have an axe to grind with everything.
I purchased a set of ingress V1 when he first started out, and they were quality made, but the design didn’t follow the cup profile needed, so I outsourced a local shop to have them made (prob 25-30 qty) based on the larger 1" profile cut/6061. I put them under everything using the .5" marble slab for the smooth surface. Even speakers (at the time). I also use inner tube for the vertical, so its rack > inner tube > MDF > cup/bearings > marble > component. Works like a charm! Although with heavy speakers now, I opt’d for the GAIA’s
However, the inner tube does present some challenges one of which is maintaining their pressure. So I used a tube inlet extender which then gives you the ability to inflate/deflate without having to remove the components. I researched a ton on bladders (square ones like acoustic revive $$) and small inner tubes that are used on those small IC cars/toys etc.. but time is always a challenge and never took it farther then the bike inner tube.. These look to be great idea, but as usual in this hobby, ridiculous cost http://pneuance.com/. I would like to made two adjustments to my platforms: 1. Being the other challenge with inner tubes are getting the correct psi based on the component weight, its basically a guess (by eye) and putting just enough air that the tube isn’t grounding out on the platform. To that end I would like to try some wave washer/comp springs instead of inner tubes and just started looking/researching. Since you can then design around the max load per spring, it should be easier.. 2. Replacing the marble with say a .25" plate of alum and then maybe some cork or wood on top. The marble works but the heavier components give me pause and would feel better with a more structurally sound formula. Something like the symposium segue platforms come to mind, but not sure if that would be too compliant and would need about 5 so that is costly
It’s probably not that obvious but worth pointing out since inner tubes were just mentioned. The smoother and harder the surfaces are made for the roller bearing assemblies the more critical balance and level become, even if cups are used top and bottom, as I pointed out a couple posts down. Therefore, I humbly submit inner tubes are not (rpt not) a good choice for vertical isolation with roller bearings, or even used alone. Steel springs like you know who’s are a much better choice, not only because of the leakage issue but because inner tubes have a very non-ideal geometry for pneumatic isolation - the ideal geometry being tall and slender. I.e., large volume of air v per surface area in2. As I also just got through mentioning, there is some degree of vertical isolation with ONLY roller bearings and cups. Which reminds me, the reason some components can be mounted directly on bearings with no cups is probably because the hard roller bearings make slight depressions in the metal of the chassis base.
@redlenses03, if you want pneumatic isolation, and don’t mind spending a little money and time, you can keep your eyes open for the old Townshend Audio Seismic Sink platforms that were made in the 90’s-00’s. There were a few different versions, but they all shared the same basic design: an inner tube inside a top and bottom steel plate structure. The inner tube is inflated just enough to keep the top and bottom plates from touching; the lower the P.S.I., the lower the resonant frequency and the greater the isolation. A set of roller bearing on top of a Seismic Sink provides isolation is all planes.
Or, you can get the current Townshend Audio Seismic pods, but they’re around $100 each. Sets of Pods for a complete system can add up to quite a bit of money. But then two sets of the IsoAcoustic Gaia I’’s---enough for a pair of heavy loudspeakers---will cost you $1200, more than two sets of the Pods. The GAIA II is $600 for two sets, the GAIA III $400. Not too bad if you have light (under 70 lbs.) speakers.
bdp24 redlenses03, if you want pneumatic isolation, and don’t mind spending a little money and time, you can keep your eyes open for the old Townshend Audio Seismic Sink platforms that were made in the 90’s-00’s. There were a few different versions, but they all shared the same basic design: an inner tube inside a top and bottom steel plate structure. The inner tube is inflated just enough to keep the top and bottom plates from touching; the lower the P.S.I., the lower the resonant frequency and the greater the isolation. A set of roller bearing on top of a Seismic Sink provides isolation is all planes.
>>>>>Actually there is what we call a design pressure for pneumatic iso stands, as it turns out the *ideal pressure psi* is not (rpt not) the minimum pressure psi, but something in between very low pressure and very high pressure. Otherwise the inner tube is too floppy and won’t act like a spring. You have to hunt for the ideal psi by ear. On my original single airspring Nimbus sub Hertz platform with 0.5 Hz performance the ideal pressure was around 30 psi for a load of 30 lb. For higher loads, the ideal pressure would go up, 🔝depends on the load. Also, inner tubes can’t provide effective isolation in the horizontal plane 🔛 or in any of the rotational directions. 🚁 since the inner tube is quite stiff in those directions.
Inner tubes also have too much internal friction/damping for my taste and there’s the leaking problem as well.
@geoffkait am aware of the challenges of inner tube in both setup and performance as you eluded to - has to be just right and thus my reference to trying wave springs etc..just not sure what and where to get them yet, ideas?
Additionally, substitutes for marble that I currently use, especially for heavy monos (which I don’t for those and use a top and bottom cup with MDF due to their 90lb weight
@bdp24 Have considered the Townsend products (would love to try them) especially the platforms for speakers but like you stated are costly.
I do use the GAIA’s on my spkrs and although not super inexpensive, they do perform very well. Priorities really and one has to pick where to focus $$. Currently looking to upgrade DAC sooo...
I do do keep an eye out for their products used, but rarely come up, at least for my application and or timing.
redlenses0 @geoffkait am aware of the challenges of inner tube in both setup and performance as you eluded to - has to be just right and thus my reference to trying wave springs etc..just not sure what and where to get them yet, ideas?
>>>>I design high carbon heat tempered, cryo’d compression springs for moderate loads 25 to 70 lb and Super Stiff Springs for heavy loads, 75-200 lb. Both types of springs are suitable for placing directly under a component. Performance circa 2-3 Hz.
geoff kait machina dynamica vibration isolation and resonance control
@uberwaltz, Barry Diament wrote that the roller bearings made more difference under his Maggie 20.7’s than under his electronics. But then he uses all solid state stuff, and records in digital. He uses the 20.7’s as monitors! You can see them on his website. He bolted the stock Maggie feet onto a 2’ square piece of plywood, then put a trio of bearings under the plywood. What I wonder is if he puts the bearing cups right on his carpeted floor, or on top of something else.
I have my Eminent Technology LFT-8b’s bolted onto Sound Anchor stands, which are a tripod design (inherently more stable than four feet, as found on loudspeaker outriggers). The SA’s come with spikes, but a set of roller bearings, GAIA’s, or Townshend Audio Seismic Pods can easily be substituted, which is what I intend to do. The Pods would run about $600, the GAIA II’s (good up to 120 lbs.) also $600 (they come in packs of four, so I would have two left for some other application), the Ingress V.2 only $140 if used single-cup style. The V.2 plus a set of Geoff’s springs would make a great budget isolation system. @geoffkait, how do you recommend your springs be partnered with roller bearings? I may just use my Symposium Jr’s, double cup style, therefore not having to be concerned about the LFT’s rolling off the bearings!
bdp24 The V.2 plus a set of Geoff’s springs would make a great budget isolation system. @geoffkait, how do you recommend your springs be partnered with roller bearings? I may just use my Symposium Jr’s, double cup style, therefore not having to be concerned about the LFT’s rolling off the bearings!
My “budget” springs having been outperforming high priced isolation systems for more than 20 years, and have been used in some of the most outstanding systems at CES including Mapleshade, the big Tenor Rockport system and two John Curl Bob Crump systems. My springs have gotten less expensive over the years as I learned how to simplify and evolve the design. Anybody can over-engineer spring-based isolation system. It’s not rocket science. 🚀 My springs have isolated Verdier turntables, 200 lb Flagship Classe amps, $30K high power BSW Consulting tube amps, Lamm tube amps, great big VPI turntables, Raven turntables, and many other high end systems. By going to a smaller high-performance spring I could dispense with everything else - the two plates, the dampers -and use only the spring. Make sense? Wasn’t it Einstein who said a thing should be made as simple as possible?
Thinking on I still have two 16x16 x2 maple blocks from previous speaker endeavors. I could fasten the Maggie's existing feet to them and roller blocks then under that. Right now they would be direct into carpet.
I would imagine damping would be more appropriate as well as less expensive for dipoles since speaker isolation is primarily used to prevent mechanical feedback. And dipoles don’t transmit much energy directly to the floor. It would probably be much more cost effective to isolate the front end.
In looking at the diagram blowup of the GAIA on the IsoAcoustic website, I came to the conclusion that whatever isolation they are providing must be by way of some sort of rubber. They say it's not Sorbothane, but may it be Navcom? That stuff is still being made, and is used in firearms and other fields as mechanical dampers. I doubt it's the EAR rubber, but who knows?
I hope it's not, as the isolation properties of rubber doesn't extend very low in frequency, which is what we want. The lower the better. But remember when everyone ditched the springs in their VPI HW-19 tables for the SIMS Silencer Navcom pucks? Not all springs are created equal, and I don't think Geoff is going to share his secrets!
If I had the dough, I'd have a Herzan or Minus K under everything. Audiogoner folkfreak has his table on a Herzan (he had me over for a listen), and it's a thing of beauty!
@uberwaltz and @elizabeth, the idea I came up with when I first saw Barry Diament's big Maggies on roller bearings, but transferred to my carpeted room and the pair of Tympani IVa I thought I would be able to shoehorn into that room (alas, that was not possible :-( ) was this:
Make a base plate out of Maple/Baltic Birch plywood/etc., and install three spikes in it to raise it off the carpet enough to make it stable (three is inherently stable, four a chore), and level it. Mount the Maggie feet/stand/base plate onto a similar piece of wood (may as well make it the same size as the one on the floor), and place the wood-mounted Maggie on top of the base plate/bottom piece of wood, with a trio of roller bearings between the two boards.
The same can be done with Geoff's springs, or even with both, using another board. Wood is cheap!
No offence taken, perhaps because I don't know what you meant ;-) .
Say, are ya gonna tell us why the roller bearing is no good for isolating a turntable? I haven't come up with anything better than the spinning moving mass of the platter pulling the ball bearings in the direction it is spinning (clockwise).
@geoffkait got snapshots of those springs. Sure would be nice if we could post pics. Things would be so much easier to comprehend. I used the bike inner tubes under maple plywood bases for about a year. Once the component was placed on top of Barry's "economic" hip joints, some of the platforms were well balanced while others were a little lop-sided due to heavier innards more toward a side, the front or the back. Sliding off? For me none ever did.
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