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Hi there,I have a Lovan classic rack. The tubes are fillable. I am debating if I should mass load the stand with lead shot and/or sand or go the low mass route and use spray foam instead.
Any input would be appreciated.
Thanks.
Follow Ups:
Thanks for all the input everyone. I've got some idea now how I should proceed.Thanks again.
IME with Lovan racks, the steel is too thick to be adequately damped by compressed polyester batting, no matter how tightly you pack it. Foam would be even lighter and less effective.I use oil-absorbant clay granules in the legs, similar to cheap kitty litter, but cheaper if bought at an auto parts store. Be sure to caulk the openings at the bottoms of the legs before filling. This stuff is dusty but not toxic like lead. It is somewhat lighter than sand, but does a good job of damping the steel.
For the cross members, I stuffed them with polyester batting and covered the inward faces with Dynamat X-treme. Neither of these is completely effective, and the two together work better than either treatment alone.
The top shelf vert legs (of the 4 indiv shelves) are filled with BB's...the .177 caliber copper plated lead-center one's used for kids BB guns. It costs a lot more than sand, but the mass is excellent and my TT sounds really good. I figure the copper balls sound better vibing against one another verus lead balls.The bottom 3 shelf legs are filled with sand, which isn't bad - the BB shelf weighs 2x as heavy though. a few granules will come out of the spikes occasionally when you have to move the rack shelf-by-shelf, but not a big deal. I also plan to cut up some strips of Dynamat and lay it on the inside of the 3 horizontal shelf supports that can't be filled...so the dynamat won't be in plain sight.
just pop the plastic covers off the vert leg tops to fill them, they aren't plued or permanently attached.
AlSO, try grounding your rack. attach small 3" long wires to each shelf (at the back leg) with tape and run one long wire from the bottom shelf to your preamp's ground lug. the noise floor drops quite a bit for me, and i haven't scraped any of the finish off to get to bare metal. a great free tweak.
As is, my rack won't move even if shoved really hard...it cost about $10 to fill the 3 round legs of one shelf w/BB's. they are illegal where i live though, so ebay was the only place to purchase them!
a side note, on my Lovan Classic the bottom shelf is about 12" tall. i recently moved this shelf to be the 2nd from the top due to a new preamp that's really tall...the configuration works great & doesn't look funny.
You can try searching here under my name for posts on this around 2000/2001. At that stage I had a Lovan Classic rack and I tried various options and reported on my experience.I did spray foam into the cavities of the horizontal members through the open holes underneath them. It worked but it was messy. The foam expands after spraying and it's pretty well impossible to guess the right quantity. The result is that it starts expanding up out of the holes (I had the rack upside down to do this) and it gets over the outside of the members. It's difficult to clean off, and I never figured out a way to remove it. I think it helped but I don't have any comparisons to report.
With the legs I tried lead shot which I eventually removed and replaced with polyester batting rolled up tightly and forced into the legs through the top. If you remove the spikes and insert a long metal rod through the hole for the spikes, you can tap the brass caps out which makes filling the legs much easier, provided you put the spikes back in first. I didn't try sand in the legs because there were gaps around the bottom plates where sand would have leaked. I found the added mass of the lead produced a mid bass emphasis. The polyester provided damping without the mid bass emphasis, which allowed me to hear a bit more low bass extension that had previously been masked.
If you want to use sand in the legs, you're going to have to make sure the bottom plates are fully sealed.
My preference would be to go with something light like the polyester batting which needs to be tightly compressed to work well. It's a better option for the horizontal struts than the foam because you can remove it if you don't like it, though it would be difficult to get it all out. I think it's basically impossible to remove the foam once you've got it in there. With the legs you can try the shot or the polyester and see which you prefer. I suspect if you like a lot of 'slam' in the bass you'll prefer the shot. On the other hand, if you want a bit more natural bass without that kind of emphasis and with a bit more extension, then go for the polyester.
A lighter fill than lead, say one of the fine steel shots used for sandblasting or something like the Atacama Atabytes, should produce results somewhere in the middle and I think would be preferable to lead. It also won't have the health issues that lead does.
Thanks David,So, with the polyester, if I have enough room, like the hole on the top of the lovan supports, can I just roll up a big piece and shove it in and repeat until no more will go in or do I need to cut smaller pieces?
I'm ordering some Skylan stands for my speakers as well. The top and bottom plates are mdf, the 2 columns (per stand) are extruded polymer. Would you suggest filling them with the same polyester batting?
Measure the fillable depth of the Lovan leg you want to fill and then cut a long strip of polyester batting that width. Roll it up very tightly to see what length you need in order to get a roll the diameter of the inside of the leg. Cut one piece that size first to try.Roll the batting tightly and simply start stuffing it into the leg. It won't move down easily and you need to use something like a long screwdriver blade pushed into it at the lip of the opening to help you slide the polyester down inside the cavity. It takes a bit of time but you can get thee.
I have no experience with the Skylan stands so I really can't comment on them. When in doubt I tend to start with the manufacturer's recommendation and then experiment if I'm not happy.
At the stage that I originally filled my Lovan with lead shot, I thought mass loading was the only way to go and I hadn't heard of any other approach. Then I started hearing about the light and rigid school of things, removed the lead and tried the polyester, and was converted. I ended up designing my own rack based on that approach. Next I got Dynaudio Contour 1.3 SEs with a pair of older Dynaudio stands that had the legs filled at the factory with something heavy and started to wonder whether mass could work in some places. Eventually I replaced my own rack with a Grand Prix Audio Monaco base unit and filled the legs of it with steel filling because they recommended mass loading and I was reluctant to use lead shot again simply because of the health issues associated with lead. The mass loading helps with the Monaco and I sometimes wonder whether things would improve with the added mass that lead would bring,
Overall, I think lead isn't much of a risk once it's sealed in the legs of a rack but I used to work in the health and safety area so I am a bit cautious. Also, while I can make decisions about things like lead for myself quite happily, I'm less happy about making a decision that could affect other people living in the house so these days I tend to avoid such options on principle. The copper coated BB shot that someone else mentions would be much safer since the lead is sealed under the copper.
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