Lowrider asked,
"@geoffkait , interesting.
"OUR NEW PRODUCT!! - Super compressible MINI ISOLATORS - VERY LOW RATE SPRINGS FOR ISOLATING REALLY LIGHT THINGS."
Are these springs heavy enough to stand on their own? Will a board placed on top with a component be stable?"
I have several types of springs. They should be used in sets of four or more. They are very stable when used with the proper weight. They are especially stable being low profile compared to larger springs I used to sell. As I said earlier the springs will isolate any component - with or without a board - weighing from 1 lb to 250 lb, depending on which spring is selected. Obviously the heavier the component the stiffer the spring has to be since you obviously want to avoid compressing the springs to the point where the coils start to touch. If you use a board you need to add the weight of the board to the weight of the component to get total weight so I know which springs to send. For example, a preamp weighs 8 lb and the board weighs 4 lb, the total weight is 12 lb. Thus 3 or 4 of the medium stiffness springs will be appropriate for that load.
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Spencer wrote,
@geoffkait
Every post you write should be signed like this:
"Geoff Kait
machinadynamica.com"
Anything less is a lack of disclosure and doing a disservice to this community. You've been around long enough and involved in enough controversy to know better.
It's a shame this has to be brought up again.
Cheers,
Spencer
It's actually never been brought up before. I thought everyone knew me. Thanks for being Johnny on the spot, Spence.
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@geoffkait
Every post you write should be signed like this: "Geoff Kait machinadynamica.com" Anything less is a lack of disclosure and doing a disservice to this community. You've been around long enough and involved in enough controversy to know better. It's a shame this has to be brought up again. Cheers, Spencer |
@geoffkait , interesting.
"OUR NEW PRODUCT!! - Super compressible MINI ISOLATORS - VERY LOW RATE SPRINGS FOR ISOLATING REALLY LIGHT THINGS."
Are these springs heavy enough to stand on their own? Will a board placed on top with a component be stable? |
"Geoff---When you say "I can do it cheaper and better" and "My springs are the lightest in the business", may I take that to mean you market such a product? Can you direct me to a site, or provide contact/product info?"
I've been in the business of isolation and vibration control for 20 years as well as many other things. Currently I offer small steel springs of different spring rates for isolating anything from one pound to 250 pounds. These springs are very low profile so can even be used on submarines. ;-)
Geoff Kait
machinadynamica.com
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With a preamp that light, just like a small phonostage, or DAC, what-have-you, you need to be aware of not "loading" the preamp chassis with a heavy mains cable dangling from it, causing an energy path from whatever the cable is also in contact with. Again this is where those shot filled bags could be placed above and below the mains before it enters the preamp to "unload" its effect.
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Besides isolation from room vibration from below, you must effectively wick the energy out of the component cabinet as well. adg101 had the cheap isolation aspect nailed! IKEA bamboo chopping/cutting boards are a no-brainer!
Bamboo composite board is rather sophisticated in its combination of polymer/grass density layering and is light, stiff, 18% more rigid than hard rock maple, and will be less likely to store low frequency energy. Not to mention, green and cheap.
The moongels may well do the trick over an audiophile BrightStar Isonodes or other gel gumdrop type footer. These are great below the board, but you will want to couple (wood blocks(to chassis/not under feet), point, etc) the cabinet/chassis of the component to draw either internal energy or airborne acoustic energy from the sheet steel box.
Mass loading on top of a component is advised, if possible for its dampening and absorption properties. Something I have found most effective for this, I no longer know where to source. They were paperweights, leather bags filled with lead shot, used to hold down large architectural roll size drawings. Perhaps diving ballast bags would do the trick and be most cost effective.
Once you eliminate the smearing that these vibrations cause with, cheap DIY solutions, I believe there is no doubt you will be well rewarded, perhaps amazed by the results. Your system background will become way blacker as well. I’ve employed these methods for years on my digital course, tubed preamp, and tubed phonostage with excellent results. I realize your Atma pre offers very little room on top to try to mass load, is it the UV-1 UltraViolet?
Happy Listening! |
Geoff---When you say "I can do it cheaper and better" and "My springs are the lightest in the business", may I take that to mean you market such a product? Can you direct me to a site, or provide contact/product info? |
Lowrider57 wrote,
"@geoffkait, I thought they might be "spongy" like the 1/2 tennis ball concept."
-- tennis balls or 1/2 tennis balls don’t have the right spring action to act like a real spring either. You actually need to match the spring rate of the springs to the mass of the component. I’m not saying tennis balls or bicycle inner tubes or gooey type devices won’t do anything, I’m just saying they’re just not as effective as real isolation devices, like my springs. While gooey or rubbery type materials like these or say Sorbothane might seem like good materials, even perfect materials for audio applications, they seem like such a good idea, right? But they are a pig in a poke. You will do much better with mass on spring plus very hard materials to support the iso device and to support the component on the iso stand, generally speaking. It has been 20 years since the Vibraplane iso stand blew into town. That changed everything.
"The ad goes on to state...
IsoNode feet are specially engineered from a unique polymer that rejects a wide range of vibration trying to enter from underneath the component. The highly compliant IsoNode acts as both a liquid and a solid for superior vibration control. Vibration and resonance that could interfere with the performance of sensitive electronic circuitry are converted instead to extremely minute amounts of heat and harmlessly released."
-- They are apparently viscoelastic in nature and act together with the load as constrained layer dampers. I’m not saying they won’t work to some degree but to deal with very low frequency vibration you need real isolation, as opposed to "vibration control." You can have both, which is why they suggest they can be used UNDER a real iso stand. At least that’s what they say. How you should support a real (mass on spring) iso stand is another issue unto itself as well as how you should mount the component on the iso stand.
"BTW, I googled "mass on spring" and I see that the spring has a non-negligible mass."
-- A spring (steel spring, air bladder or bicycle inner tube or air spring) would usually be what, 1/100 the mass of the component being isolated? Where I come from that’s negligible. My springs are the lightest in the business, coming in at around 1/200 the mass of the load.
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I run my ModWright LS 36.5 on 3 Daedalus DiD,s isolation devices on a bamboo cutting board from Ikea "Lamplig" on 4 RTOM Moongel dampening gels on my rack. The cutting board and gel pads are very affordable and made a difference but the DiD's on their own are incredible. I wasn't having any issues with noise but per Dan Wright's recommendation tried the DiDs and am floored how they have elevated the sound of my 36.5 to another level. The 36.5 is great on its own but with the DiDs, piano, cymbals, brushes on a snare are much cleaner and have longer decay: the 36.5 breathes more... more open.
Try the IKEA Lamplig with the Moongels first. They're cheap. The cutting board has a grove on one side so face that side down and place four Moongels to the inside edge of the grove. This tweak with shipping is less than $40. The DiD's are $160 ea. and worth it. I only have one set but will be getting another set for my CD player. I tried them under my CD player and they work there as well but the improvement was much greater on my tube preamp. I'm using Herbie Tube Dampers so I was a little surprised how drastic the DiDs improved things.
If you live close to a Guitar Center or any drum shop you can get Moongels there. Us drummers use Moongel on cymbals and heads to control resonances. Try just the Moongels under the feet of your pre first to see if that alone works. A package of six gels is $7. |
Thanks for stating your experiences, Al. And as far as my thoughts on "sympathetic vibration" go, you're right about the different tube types and the use of tube dampers. The Rogue used 4 12AU7's which are low noise and rarely microphonic.
In both cases, with the Rogue and the Atma-Sphere, I've removed the stock feet. As mentioned earlier, the only solution to remove the noise with the Rogue was to isolate beneath the unit and mass load on top.
I wonder if the new lightweight preamp should sit on some MDF with isolation footers between the pine and the MDF.
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The preamp sits on a shelf enclosed in thick wood (pine) open in front and back. If the shelf is tapped on, it may create resonances surrounding the unit thru the sides and shelf above it. These resonances may be picked up by the exposed tubes which are in close proximity. (The shelf is 10" high with enough room for air to circulate).
That would explain why a 30 lb. Rogue preamp picked up noise from tapping on the shelf. Does this theory make sense to anybody? I think what you are referring to is known as a "sympathetic vibration" effect. I suppose the possibility can’t be completely ruled out, but it seems to me to be unlikely. In part because the tube types in the two preamps are different, and also in part because you’ve been using tube dampers. Also, I’ve had many different tube components on pine shelving over the years (what is referred to as 1 inch pine, which is actually about 3/4 inches thick), without a lot of space around the components, and without ever having that kind of problem. Although I don’t think the tubes in any of those components were quite as exposed as the ones in your two preamps. (I have used anti-vibration products under the feet of many of those components, btw. The particular products I’ve used are no longer made, however). I have no particular knowledge of or thoughts about the IsoNode feet. Best regards, -- Al |
@geoffkait, I thought they might be "spongy" like the 1/2 tennis ball concept. The ad goes on to state... IsoNode feet are specially engineered from a unique polymer that rejects a wide range of vibration trying to enter from underneath the component. The highly compliant IsoNode acts as both a liquid and a solid for superior vibration control. Vibration and resonance that could interfere with the performance of sensitive electronic circuitry are converted instead to extremely minute amounts of heat and harmlessly released.BTW, I googled "mass on spring" and I see that the spring has a non-negligible mass. |
Lowrider,
according to the blurb for the IsoNodes they are vibration control devices as opposed to real (mass on spring) isolation devices. They are not springs nor do they act like springs, in other words. They are apparently some sort of viscoelastic damper. No offense intended to IsoNodes.
"IsoNode Large Isolation Feet are 1.25" wide and .75" tall and are great for integrated amps, preamps, DVD players, CD players, and more. Use them by themselves or with other isolation accessories such as platforms. Adhesive backing is included for easy attachment and positioning on your components."
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Thanks everybody for the input so far, but I have a theory... both preamps have exhibited the same problem; both have an exposed tube design on top of the unit. The preamp sits on a shelf enclosed in thick wood (pine) open in front and back. If the shelf is tapped on, it may create resonances surrounding the unit thru the sides and shelf above it. These resonances may be picked up by the exposed tubes which are in close proximity. (The shelf is 10" high with enough room for air to circulate). That would explain why a 30 lb. Rogue preamp picked up noise from tapping on the shelf. Does this theory make sense to anybody? @geoffkait Ok thanks, I understand the concept of "mass on spring" now. In addition to the Mapleshade Isoblock 1, following this concept, there are Bright Star IsoNodes for isolation... http://www.audioadvisor.com/prodinfo.asp?number=BSISO&variation=L4IYO, would these be a good size and provide the right amount of spring rate? @almarg , Al, as a test I used a wad of bubble-wrap as a cushion under the IC's and was unsuccessful. |
"The cheapest way to get great isolation: two Baltic Birch plywood shelves with a barely inflated bicycle tire between them, with a trio of roller bearings between the pre-amp and the top BB shelf (this design courtesy of Barry Diament). If you have the dough, a Minus K platform ($2500 or so). Alternative: a trio of the Townshend Audio Seismic Pods (about $750, I believe)"
i can do it better and cheaper. The issue with the bicycle inner tube approach is that the surface area of the air bladder/spring is too large relative to the volume. To maximize isolation effectiveness the surface area of the air spring or bladder must be minimized. Besides, a barely inflated inner tube doesn’t provide sufficient pressure/spring rate to actually do anything. That’s kind of the whole point of mass on a spring isolation.
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The cheapest way to get great isolation: two Baltic Birch plywood shelves with a barely inflated bicycle tire between them, with a trio of roller bearings between the pre-amp and the top BB shelf (this design courtesy of Barry Diament). If you have the dough, a Minus K platform ($2500 or so). Alternative: a trio of the Townshend Audio Seismic Pods (about $750, I believe) |
Al wrote,
"Lowrider, I’d suggest trying Mapleshade Isoblock 1’s, or the lower priced generic equivalent that I think may be findable at Home Depot or elsewhere. Assuming that their 1.75 inch height can be accommodated. I say this even though the description recommends that they be used only in conjunction with isolation platforms."
Ah, the age old conundrum, should I isolate or should I couple?
;-) |
Lowrider, I’d suggest trying Mapleshade Isoblock 1’s, or the lower priced generic equivalent that I think may be findable at Home Depot or elsewhere. Assuming that their 1.75 inch height can be accommodated. I say this even though the description recommends that they be used only in conjunction with isolation platforms. Also, are you certain that the mechanical pathway by which shelf vibrations are affecting the preamp is not via the interconnect cables that are connected to it, that are probably resting on the shelf behind the preamp? Best regards, -- Al |
@geoffkait , what do you mean by mass on spring?
Any any isolation device that employs airsprings, mechanical springs, tennis balls, bungee cords, etc. operates as a low pass mechanical filter for vibrations, where the component represents the mass. The springs are selected in terms of how springy they need to be according to how much mass is to be isolated. So for very heavy components the springs would have to be very stiff, otherwise they would compress too much under load.
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@geoffkait , what do you mean by mass on spring? |
It's not the tubes. It's a new Atma-sphere pre, new tubes, and I have also rolled in some other tubes. IMO, the unit needs to absorb vibration or be decoupled from the shelf.
My previous Rogue preamp, also with exposed tubes, experienced the same problem. (it weighed 30 lbs.). I used Herbies as footers and also mass loaded the top to stop the vibration.
It's similar to a footfall issue. |
It sounds like a microphonic tube. No preamp should be so sensitive to vibration that merely touching its shelf generates sound through the speakers. |
I have one word for you, mass on spring. Almost all effective vibration isolation solutions employ this simple technique. |
