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I just added some Dynamat to the inside faces of the horizontal members of my Lovan Sovereign rack frames. Thanks and honors to David for posting this tweak a couple of years ago.Filling the vertical members with oil absorbant clay (larger grains than sand and not as heavy, but very effective at damping the tube's acoustic resonances) helped, and according to my wife, even improved the clarity of the sound of the TV located near the rack, but putting the Dynamat on the horizontal members pushed the performance over the top!
I'm sure the results depend on the particular equipment (Wadia 861 and InnerSound
ESL 300 in my case) and the equipment's sensitivity to particular vibration frequencies. The tones of the undamped horizontal members are higher than the tones of the vertical members, so don't give up if you damp the legs and do not hear much improvement.Dynamat is cheap in audiophile terms, but one has to visit a car audio store to purchase it. Think of the experience as an opportunity for growth!
Follow Ups:
HelloMay you post some pictures of your hotrodded ovan racks ?
Which Dynamat kits do you use ?Thanks
I used the "Xtreme Wedge Pack," SKU 10425. This is a triangular box containing a single 18 by 32 inch sheet of the thicker Dynamat material. It sells for $34.95 at car audio stores that sell Dynamat products, or for $21.95 from theZEB.com (see link below). The material is rolled up like a poster inside this box, and develops wrinkles. These don't affect performance, but mean the exposed surface after treatment is not flat.It is easy to cut the exact sizes needed with tin snips. Be sure to wear gloves and work over newspaper, as the damping polymer is quite sticky and hard to remove from clothes and carpet. It helps to have a wallpaper roller to press the material onto the surface to be treated and remove some of the wrinkles.
Sorry, no photos. There is not much to see, as one point of my work has been to preserve the appearance of the rack system (high WAF!).
Al
Thanks for your advices.I will also buy a kit for my PC !
... is to simply replace those thin stock MDF shelves with some inexpensive, sonically inert, good-looking, homemade polyethylene duplicates. I had tried filling the tubes with sand and shot, and damping the stock shelves and inner framework with Dynamat. Don't even bother... There was some change in the sound then, but nothing beat the improvements wrought by these new shelves, IMO. Use three 24" x 18" x 1/2", white poly cutting boards. You can easily find them on sale in restaurant-supply stores (a chef-buddy of mine got mine for me "wholesale", hee-hee!). 1) Trace the outlines of the Lovan shelves onto them. 2) Jigsaw out the little half-dome shapes from the front corners of each shelf after trimming the rectangular dimensions down to proper size. 3) Chamfer down the rough edges. 4) Voila! I still use the stock rubber pads beneath the new shelves, but I am thinking of removing them or trying tiny rounds of sorbothane or blue-tack. Hey, I was suprised that I've never heard of anyone else trying this tweak. The sound of the highs (and mids too) are now noticeably smoother, but still well defined, at high volumes. The mid-bass has a bit more bloom. I definitely think that there were certain high-frequency artifacts being manufactured via the stock Lovan rack design, before this tweak. I also think that using aluminum cups between the spiked feet and the floor improved the sound more than Dynamatting the shelves and filling the legs. Go for it.
This has got to be better and cheaper than any other material at anywhere near the price. Solid cast acrylic could be less resonant, but would cost a fortune to purchase in the thickness needed unless one has access to a good scrap pile.
Is to (I have yet to try it...) remove the gold caps from the Lovan pillars and stuff tightly rolled foam-rubber rubber or neoprene tubing inside. I am thinking of the neoprene tubing that is used for wrapping around lawn mower handles, or maybe even that foam rubber tubing that is used for PVC pipe insulation. It would be easy to size and install and could be extracted easily as well. If the fit is tight enough inside of the frame tubes then who knows - maybe it'll work? I'll let this forum know if I try it and it works. You're welcome for the PE shelving suggestion. The standard MDF shelves seem to be a big part of the problem with the Lovan rack. And, 1/2" thick boards do come in different colors, including black. The one reservation one might have about using PE cutting boards as shelving would be the weight restrictions imposed by this material. I have no problem shelving my heaviest components which are my Sony CDP and my SOTA turntable (about 35 lbs. each), but then again I am not using the stock feet on the CDP and the TT uses only three feet as stock. With three Sorbothane "Big Feet" under my Sony and three adjustable feet under my SOTA, the weight is distributed directly over the Lovan's triangulated framework, instead of way out over the PE shelf corners. Components over 40 lbs. might need 3/4" thick boards, especially if you use four feet per component. 3/4" thick boards are slightly more costly, but can still be viewed as a relatively cheap and effective solution. Have fun.
When I originally made my isolation platforms, I first cut the platform out of ply because it was available and I wanted to see if I liked the idea. When I decided I liked it, I thought of using clear, flame polished acrylic but because of the cost I looked around for a cheap alternative to try first instead of the ply and gave a PE chopping board a try. It surprised me by working/sounding better than the wood. I then tried acrylic which I think works better again but is much more expensive.My one concern about the PE is that it is a relatively bendy material, at least in most chopping board thicknesses, so I wonder how well it would hold up under a heavy component. 15mm thick acrylic is very good in my isolation platforms and I see that Grand Prix use acrylic shelves in their megabuck platform, plus at least one other firm making isolation platforms uses acrylic.
I think acrylic is definitely superior to PE, but at more than a few times the cost. PE seems good value for the money as a shelf option provided it's stiff enough to support what you're going to put on it.
David Aiken
The 1/2" thick poly cutting boards that I'm using on my Lovan rack right now are pretty stiff and do not bend under the weight of my heaviest component, almost 40 lbs. (a Sony DVP9000ES CD player). The triangulated frame of the Lovan does pretty well distributing weightloads. It might help to move the rubber support pads around (underneath the shelves and on top of the tiangulated Lovan frame members) as needed in order to compensate for any sagging. I think that so long as the 1/2" thick poly boards are used, most people won't have a problem.
.., I forgot to mention that I have seen grey-colored poly cutting boards and poly boards thinner than 1/2" (if white color or shelves of non-standard thickness turn you off), but I'm not sure where to buy them. My 1/2" thick white poly cutting board/shelves are very rigid, and do not look that bad at all, even though they are twice the thickness of the stock MDF Lovan shelves. They do rise up over the gold caps of the Lovan pillars about 1/4". If you do a good job at cutting, smoothing, and radiussing the new cut edge surfaces of these poly shelves they can look pretty nice - certainly as good or better than some of the other tweaks proposed here. When the components are mounted on the shelves the whole setup looks fine. I've even had people ask me where to buy "...a nice-looking rack like that...".
At www.cuttingboardcompany.com you can find 24" x 18" x 1/2" poly cutting boards in colors like black or beige, so you are not stuck with white shelving if you don't like. For components over 30 or 40 lbs., it might be better to choose the 3/4" thick PE boards that The Cuttingboard Company offers on a custom-order basis. 3/4" (and thicker) boards are only offered in white, however.
I actually just removed the last traces of Dynamat from my system today and you post this! :-)I moved away from the Lovan rack several years ago now, but the Dynamat was effective in damping the horizontal members. They are actually a pain to damp because the holes through which you could insert damping materials are in the bottom face of the member, so things like sand or shot would just fall out. I eventually tried expanding foam which does work, but once it sets it's impossible to remove if you don't like it which means it isn't really a good option. The polyester batting would work and would be removable but with some difficulty given the location of the holes. All in all, the horizontal members on the Lovan rack are not the easiest to work with and Dynamat has the advantage of being effective and also being easy to apply and remove. I think ease of removal is a very big advantage when you're playing with damping because you're never really certain whether you're going to like the results until after you've tried it, and solutions like the spray foam which are pretty well impossible to remove if you find you don't like it are really not the best solutions to try.
Glad you found the recommendatio helpful.
David Aiken
I had a Sound Anchor rack here for a while, and was not impressed with the sound. It was very heavy, but still had resonant metal bits for the adjustable support struts. If I still had it, I'd try Dynamat on them.
Al,David has been recommending to me a different approach to even lighter damping: rolled polyester batting.
I have some Dynamat lying around. What does this add to the horizontals in terms of damping that a fill won't do (or is it a workaround where filling isn't possible)?
Have yet to stuff/fill my copper pipe component rack and because of horizontals, was considering the dreaded wall insulation foam spray in them. Can't get batting into them at this point, and the pipe insulating foam I originally tried was unimpressive. Don't want to go heavy. Does the kitty litter have some sonic quality that's better than sand (which is already too heavy for this use - LF)?
I used the oil absorbant because I had some, and it does not leak out of the gaps between the Lovan rack bottom plates and the leg tubing. Later I read one of David's posts where he advised against adding lead because the added mass would lower the fundamental resonant frequency of the structure. The oil absorbant is lighter than sand, so I feel lucky in my choice.The main point of stuffing the hollow structural members is to dampen the internal, 'pipe organ,' resonance of standing sound waves supported by the internal air. This the oil absorbant or polyester batting do well. The Lovan horizontal members are skinny rectangles, however, and will have a metal plate resonance as well as an internal air-borne one. The Dynamat did an excellent job when applied to the surfaces of the horizontal members that are not visible from the room. Stuffing these members may further improve the damping. It may be the case that the metal plate resonances of the Lovan members are more significant for my equipment than the 'pipe organ' ones. I won't know until I stuff them. I'm very happy with the Dynamat results.
BTW, I used the Dynamat Extreme material.
:)
I'm still stuffing some of the rack frames, and have not yet heard the Atma-Sphere amps on fully damped frames.The Wadia/InnerSound amp/Magnepan MG-20 combination has rewarded every step in damping the Lovan racks with improved separation and resolution of instrument positions in space. The biggest improvement came from damping the horizontal frame tubes with Dynamat Extreme, but filling the vertical legs with oil absorbant and stuffing the horizontal tubes with polyester batting also made definite improvements.
The Lovan shelf is somewhat resonant. The Dynamat material is too light to make much difference in the shelf tone (I applied some to the center of one shelf), but simply resting some thick sheets of Deflex on the shelf beneath the Wadia does a good job of killing its tone. The InnerSound amp rests upon Deflex sandwiched between it and a butcher-block cutting board, so that Lovan shelf is well-damped.
I should add for completeness that when I removed the racks for stuffing with the batting material, I drilled some additional holes in the undersides of the horizontal rack tubes to allow the entire length of each tube to be stuffed. I also wrapped the spike feet with "Magic Tape," a self-adhering black rubber tape sold in the plumbing department for temporary leak repairs, and filled the internal angles where the vertical leg walls overlap the leg bottoms with polyurethane construction adhesive. This stuff cures to a harder rubber than Deflex, but it damps the metal well and is cheap and easy to apply.
There is still some tone when I rap the outside faces of the horizontal frame tubes. If I were willing to sacrifice the appearance, I would apply Dynamat Extreme to these faces as well. The polyester batting is very effective at killing the internal organ pipe resonance of the tubes, but its density is too low to couple effectively to the metal.
I can see now why some people spend small fortunes on racks. The Lovan racks are not cheap, and take a lot of work to dampen completely. Some equipment responds well to the effort.
I don't think you have to eliminate all tone when you rap things. In a sense rapping things is a torture test - they simply aren't excited that much in real life use. All you really have to do is to get the amplitude of any vibration that is excited during real life use down into the inaudible level. We can never achieve perfect damping of vibration but we also don't have to achieve that. All we really need to achieve is what is good enough for our purposes in real life. If you don't notice problems from colouration when you turn the volume up to what's lud for you, you're never going to be concerned that you would have noticed them if you ever chose to go 5 or 10 dB higher or more, at least not unless you really do have a hankering to wreck your hearing permanently which I somehow doubt. Even a small bit of colouration at our highest volume levels usually isn't a problem. I know that when I decide to turn the volume up above my normal listening levels, it's because I'm after some other form of excitement than accuracy and a small bit of colouration really doesn't get noticed.The Lovan shelves are a problem and I know from reading posts here and the mention in Stereophile's Recommended Components that Kal Rubinson damped his shelves with a large helping of Dynamat. The useless little rubber dots that Lovan supply are also useless and you could try replacing them with strips or squares of Dynamat for the shelves to sit on and see what you think of that. When I moved from my Lovan, I moved to a rack I designed myself which uses no shelves at all. The components are supported directly on the frame which is 1' square aluminium extrusion internally damped with polyester batting. That made significant improvements in the sound.
I used the Lovan as a 'test bed' when trying to figure out if my idea would work. I removed the shelves and used first hardwood, and then aluminium sections tied directly to the frame in locations that would allow me to sit the components and their isolation platforms directly on them. I even tried sitting the isolation platforms directly on the Lovan's horizontal struts where I could manage it. My experience was that both the hardwood and the steel of the Lovan struts when I used them as the support added a bit of hardness to the top end which I didn't get with the aluminium which has a softer tonal signature. That's why I went for aluminium for the rack itself, and I couldn't notice any contribution from it when I changed.
Bear in mind that all this probably means is that my aluminium rack is a lot more neutral than the Lovan so I noticed a big reduction in contribution. There probably still is a contribution - I think there always is - but until I come across something better and swap again, I'm never going to be able to really hear it because I have nothing to make comparisons with. We're all in that boat: we really don't hear what's there until we actually remove it somehow.
You may be able to play around with removing the Lovan shelves and using some sort of isolation or coupling footer between your components and the frames for a bit more improvement. I actually think that while removing the resonant shelves is a big help, removing the large, flat reflective surface areas and getting rid of a lot of internal reflection around the gear is also a part of the gain you get. I do know one thing for sure, however, and that's having now eliminated shelves in my rack I would have great difficulty going back to a rack with shelves. I'm not saying I couldn't, but it would have to be a truly exceptional rack and shelf design to make me go back to something that used shelves.
David Aiken
My InnerSound amp needs a shelf of some sort to allow me to damp the motion of the power transformer, but everything else could sit on aluminum struts instead of shelves. Thanks for providing fresh ideas!
David loves perfect coupling, light but rigid as theories. Your Lovans might not work as well as his custom aluminum frames.Consider my copper pipe designs. You can make them in whatever size your heart desires very easily; only determinant of expense is the fittings, which get considerably more expensive as the diameter increases. 3/4" Ts in bulk under $.90 apiece as opposed to about $2-3 for 1" or $4-5 for 1.5". That's the way it scales upwards. Still, compared to the cost of the store bought stuff, it's very cheap. unique look, as you've seen, and stuffs with whatever you want.
As to shelving, I did a DIY alternative design to the common symposium clones detailed on Tweaks. Works very well. Works best if you have a table saw, vice, or let HD do your cutting, however. Not technically hard at all. Originally just used 16" square floor tiles, but cutting boards, marble/travertine/granite/corian also work. As I recall, your Lovans had a thick wooden or ply shelf, no?
Standard Lovan shelves are 7/16 inch thick. You may be thinking of the 2 inch thick butcher-block cutting board I have under my InnerSound amp.Copper pipe is certainly a possibility. I'm fortunate to have a superb salvage yard in town, with a good supply of square aluminum tubing in a variety of wall thicknesses. I'm tempted to try making support struts to replace the shelves from this stuff.
Ask David for a pic of his aluminum design. Since you can get the stuff from a salvage yard, you might be able to have this duped fairly well. He swears by this design.The guy above with the poly shelves has an interesting design too. Never heard anyone else mention poly boards for that purpose. Who knows? Sounds like the easiest route to better sound on your Lovans.
As to HD, they don't pipe in sound in mine. Good for fish and meat, BTW, but their audio stuff isn't your top end. Got my el cheapo KLH sub there and that was a bargain to play with. Not quite your REL, though...
The only meat I've seen at Home Depot has been from the hot dog cart out front. They have a speaker over it, and the caterwauling is too strong to permit digestion.
My Home Despot and Costco are very close together and I often make the shopping run encompass both. That's why I got confused. Or maybe they were burning cable insulation at HD and I got stoned on it and thought the hotdogs were fish. Or maybe I was getting too close to those new sake soaked wooden speaker cones and smelling the sake got me sooused? Ya just never know about people, do youse?
YOur Lovan and my DIY copper pipe rack have the exact same requirements (except for the physical shape of the cross members): both air and metallic resonance. While I would have trouble stuffing my cross members with batting at this point, I might be able to damp with foam and use Dynamat sparingly on the outside in a hidden place. I'm avoiding the kitty litter fill, because, even though it's lighter than sand by a long shot, it's still adding significant mass. And per David, low mass with high rigidity is what works best, because higher mass adds to the LF transfer. I can stuff batting into the upright members of my rack easily at this point anyway.Didn't you compare your oil absorbant to kitty litter, BTW?
Well, we use the fancy kitty litter for the rat cage. I have a partial bag of oil absorbant that resembles kitty litter, but is too dusty to use with our pets. It is fairly light-weight compared to sand. I picked up the batting this morning and will try to stuff the horizontal members with it.I used the left-over bits of Dynamat to dampen the bottoms of my glass prism cable lifters and glued them to blocks of fir in order to raise the speaker cables about four more inches from the carpet. This opens up the sound considerably. Without the Dynamat and glue, the sound got very over-detailed, but with the damping applied to the lifters, it is approaching neutrality.
Al, I'm chuckling. Maybe hamster food is our next big tweaking discovery on AA...Told ya about the height of the cable elevators off the floor. Loved the look of your beautiful prisms, but didn't seem high enough off your carpet, so I'm not surprised you got better effects with more elevation. I'm still convinced it's a static electricity phenomenon and the height up to a point matters, with actual optimum height dependent upon the flooring material itself and its static charge.
let us know how your rack filling experiments play out. Nothing like actual experience in this biz.
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