Replacement of glass wool damping in Altec Valencia

[xronx]

Hello,

I wouldl ike to replace the old cabinet damping on my Valencias since I have already problems with my lungs and want to have no additional risk in regard of glass wool fibres / dust from my spaekers.

Has anyone experiences with changing the damping of old Altecs? Which material is the most close to the old glass wool in regards of phyiscal properties / sound.

My first thought was to install sheep wool sheets instead of the old glass wool. These sheep wool sheets are offered here in Germany from a big company specially as damping for loudspeakers, a little thinner than the org. damping sheets and a little less dense. So I thought to take two layers.

Best regards

Ron

[Hoerninger]

Hallo Ron,

mit der Schafwolle von VISATON habe ich sehr gute Erfahrungen gemacht.

Eine preiswertere Möglichkeit ist Verband- oder Kosmetikswatte aus der Drogerie, sie sehr preiswert ist. man zerreißt sie mit den Fingern in kleine Stückchen.. wodurch sich das Volumen gewaltig vwemehrt . Man benötigt etwa 10 Gramm pro Liter. Ich habe mit Watte erfolgreich einen DIY-Subwoofer bedämpft.

Wenn der bedämpfte Tieftöner auch bis in den Mitteltonbereich arbeiten soll, dann würde ich der Schafwolle den Vorzug geben, da diese nach meiner Erfahrung den Mitteltonbereich nicht so stark reflektiert. Der Einfluß des Dämpfungsmaterials auf den Mitteltonbereich macht sich besonders bei dünnen Lautsprecher-Membranen bemerkbar.

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I have made good experience with sheep wool distributed by VISATON.

An inexpensve alternativ is wad from the drugstore (for cosmetic or medical use). It must be pulled into little pieces, the Volume will increas tremendously. There will be needed about 10 grams per liter. I have successfully dampened a DIY Subwoofer.

When the dampened woofer is entended to woek up to middle frequencies I would refer sheep wool as to my experience it reflects less the middle frequencies. The influence by the damping material on middle freqencies is especially noticable with thin cone material.
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Peter

[HCSGuy]

Like asbestos in a home, glass fibers are released when disturbed. If your wool pads are intact in sheets and you are not rebuilding the enclosures, I don't see fibers being released loose into the enclosure, then blown out the ports as a problem. If a rodent has gotten into the enclosure and torn up the battens so that there are small pieces floating around loose, a problem may occur. However, the act of removing the existing glass wool will certainly release glass fibers into the room as well as leaving fibers floating freely in the enclosure, which you will need to clean up with a very good collection vacuum. In my opinion, the risks involved in redoing the wool batting far outweigh any benefits you might experience.

Here's one of Steve Schell's pictures of an old Lansing with Cheesecloth stapled over the rock wool batting - You could do this, but again glass fibers will be released.

[robertbartsch]

http://www.parts-express.com/pe/show...number=260-317


Poly fill is a great product.... a tad expensive but much better than insulation, wool etc.

[xronx]

Hello,

thanks guys for your postings...The decision to remove the glass wool was already taken due to the problems with my lungs.

After thinking about the topic and searching the web on what others have done in the regard of changing the old dampening material, I already ordered 10mm needled felt mats and sheep wool mats. I will start with medium felt dampening and if not sufficient I will increase this and add sheep wool until it sound the way I'm used to.

I agree that re-moving the old material will release more fibres than a hearing a long time with these speakers...therefore I also have bought a suitable breathing mask, safety glasses, one way overalls, meters of foil to underlay and wrap what I take out of the speakers. Also I will clean my living room meticulously to remove the contaminations afterwards.

I will keep you updated.

Best regards

Ron

[jcrobso]

http://www.mcmelectronics.com/product/LS00385
You can use spray adhesive to glue it to the inside of the cabinet.

[Altec Best]

Hello, there are some good suggestions here.A simple fix that I was thinking of would be to just cover with a thin Black fabric.You would be much better off not to disturb the Fiberglass at all.As soon as it is touched it will release them into the air.Covering with fabric should hold them into the glass itself.And would maintain it's good dampening properties well.

Regards ~ AB

[xronx]

I know, that it would be better in terms of keeping the sound properties I have now, if I would stick with the old damping material and maybe cover it with fabric. But we are also talking about fibre sizes in the micron range, which can also go through the fabric easily. I know a lot of people don't care about glas wool at all and may never have any health problems, but since I already have problems with my lungs, I just what to get rid of it, to avoid any unnecessary risk.

I would like to know which material is closest to the old glas wool sheets in it'sdamping properties / sound influence. I already have 10 mm thick felt and 40 mm thick sheep wool sheets here.

best regards

Ron

[Altec Best]

I know, that it would be better in terms of keeping the sound properties I have now, if I would stick with the old damping material and maybe cover it with fabric. But we are also talking about fibre sizes in the micron range, which can also go through the fabric easily. I know a lot of people don't care about glas wool at all and may never have any health problems, but since I already have problems with my lungs, I just what to get rid of it, to avoid any unnecessary risk.

I would like to know which material is closest to the old glas wool sheets in it's damping properties / sound influence. I already have 10 mm thick felt and 40 mm thick sheep wool sheets here.

best regards

Ron

Hi Ron, I don't know how well cotton batting would work, but it is a lot healthier than fiberglass and cheap enough too.Kind Regards ~ John

http://cgi.ebay.com/Cotton-Batting-R...item5ad98ecf4b

[Sootshe]

I replaced the original fibreglass damping in my 19's with 50mm dacron wadding. Dacron is what they use for filter material in aquarium filters & also for the stuffing in furniture......very safe. I can't say that it sounded as good, but it was very close & would be a good compromise of sound versus safety.

[badman]

There's a product called ultratouch, used for in-wall insulation. It's made of recycled denim, doesn't support fungal growth, and is not a health hazard. It's also an excellent cabinet filler/liner, and green. Big hardware warehouses can special order it, some places stock it. Let your fingers do the walking. In SoCal, Ganahl Lumber stocks it.

[cooky1257]

Take some hairspray and spray the filling liberally-should go some way to holding loose fibres during removal stay out of the room for a bit to avoid any irritation from the spray itself. Cut up a duvet and staple to the inside walls-very effective and cheap.
Cooky

[Steve Schell]

I remember attending a county fair years ago. In the building where the wool growers (ranchers? harvesters?) were competing, there were bins full of raw wool, right off the sheep. It was thick, heavy, and gooey with lanolin. It felt incredible. I remember thinking at the time that this unprocessed wool would probably be ideal for speaker enclosures. I'll bet that, purchased on the farm, it might also be cheaper than most other solutions.

Have there been any recent studies that confirm that glass fibers constitute a breathing hazard? The common assumption is that it must be terrible for health, but I suspect this results from people feeling itchy after touching fiberglass. The last time I checked into it the results were inconclusive at worst. My listening rooms have been acoustically treated with dozens of square feet of R-19 insulation for thirty years now, uncovered for most of that time, with no ill effects so far.

[Altec Best]

My listening rooms have been acoustically treated with dozens of square feet of R-19 insulation for thirty years now, uncovered for most of that time, with no ill effects so far.

Hi Steve, you must have a back scratcher on each arm of the arm chair in your listening room. Just thinking and looking at that insulation would have me running out of that room with me scratching my skin right-off. Like I have just laid in a patch of poison ivy

[xronx]

There is the clear opinion from experts, that the smallest fibers of glas wool can go into your lungs and stay there for a long time, which can cause serious health problems, therefore there are strict guidelines for health protection when working with it. Since there is a constant mechanical influence due to the moving air inside a speaker it is most likely that there is some fraction of fibres which is blown into the room. Thats why almost no one uses glas wool for non closed speakers anymore. Anyhow, I just want to have no additional risk whatever experts may say.

Actually I replaced the old stuff and covered the inner surfaces with 10 mm felt sheets (made out of old clothes). This is used as only damping in some commercially available speakers of comparable type and size. But in my case, with this only the sound was rather in-homogeneous, added sheep wool sheets (40 mm thick, made by a German company esspecially for speaker damping) on one side, the back and in the bottom helped to get a more even frequency response...at least from my first observations. I will fine tune, which is rather easy since the bass reflex ports are big enough to stuff the wool sheets through it. Therefore the effect of added or removed damping is relatively easy to evaluate.

If this doesnt lead to full succes I might try out sheep wool sheets only in accordance to the old layout of glas wool sheets. Unfortunately sheep wool and glas wool have quite different damping properties as i have read, even if thickness and appearance are not that differen.

Best regards

Ron