What do your ear's prefer stuffed in speakers and subwoofer boxes?
I bought the smallest bundle of rockwool I could find. It must be the family sized. For box stuffing and acoustic treatments.
How do you keep that where you don't want it? Ie in speaker motors and in moveable parts. This applies mostly if it can hinder cooling.
I bought the smallest bundle of rockwool I could find. It must be the family sized. For box stuffing and acoustic treatments.
How do you keep that where you don't want it? Ie in speaker motors and in moveable parts. This applies mostly if it can hinder cooling.
Personally prefer OC 703 duct board mounted using felt roll roofing nails or similar to hold in place and/or OC fiberglass roll insulation for walls, ceiling joists, etc., depending on width, thickness required.
Historically, cheesecloth was used to loosely cover components and in recent times where loose fill is desired it's put in any sort of breathable (bulk onion, etc.) bag suspended from the top or tacked, glued, etc., in place.
Historically, cheesecloth was used to loosely cover components and in recent times where loose fill is desired it's put in any sort of breathable (bulk onion, etc.) bag suspended from the top or tacked, glued, etc., in place.
I am planning to use recycled denim insulation in my speakers. It is said to have better damping than fiberglass, and I've seen it used in pro-audio. But I don't know if it is noticeably better. I have seen ported speakers blow their stuffing out the port, so I'd rather that be cotton fibers than fiberglass or mineral wool.
I grabbed some fiber glass mesh with 1/8" perforations to pin over a single layer. To act as a barrier that holds it down. The box is sealed and I got it how I like with a mere 1 1/2" layer covering just the bottom panel. As long as rockwool particles don't make a mess or get in to the sub assembly or hinder cooling.
Please read the safety regulations in your area, fiber glass is a known carcinogen, rock wool is safer.
Hollow polyester fibers used for pillows may be suitable, as they are not affected by moisture.
Hollow polyester fibers used for pillows may be suitable, as they are not affected by moisture.
The material is usually placed tight against the cabinet walls, but in some cases a layering might be desired. If it’s the soft wool material it can be fixed to the walls using the hammer type staples.
Fiberglass insulation does work, but it’s messy and requires some basic personal protection like glasses, mask, gloves, long sleeves. Polyester pillow fill is safe, but where I’ve used it in a friend’s subwoofer it had to be crammed full and packed tight to really work.
OC 703 and 705 are not usually available for sale to the general public in Canada unless you buy through an industrial contact and order a minimum quantity. You are bound to come across dead links on other forums telling you where to buy it.
The alternative is excellent; Comfortboard 80 is available at Home Hardware in 1.5” thickness, 2”, and 3”. They normally stock 1.5”. I also use Comfortboard 80 in 3” thick acoustic panels and it is very good all the way down through the midrange and into the upper bass.
Fiberglass insulation does work, but it’s messy and requires some basic personal protection like glasses, mask, gloves, long sleeves. Polyester pillow fill is safe, but where I’ve used it in a friend’s subwoofer it had to be crammed full and packed tight to really work.
OC 703 and 705 are not usually available for sale to the general public in Canada unless you buy through an industrial contact and order a minimum quantity. You are bound to come across dead links on other forums telling you where to buy it.
The alternative is excellent; Comfortboard 80 is available at Home Hardware in 1.5” thickness, 2”, and 3”. They normally stock 1.5”. I also use Comfortboard 80 in 3” thick acoustic panels and it is very good all the way down through the midrange and into the upper bass.
FWIW, etc., before the big box stores began selling OC 700 series I got scraps from a local heat/AC duct installer for free since it saved them the hassle/cost of recycling, otherwise for stuffing it was the original itch-less Miraflex.
The batting used in upholstery works very well. Just staple it loosely to the interior walls with as few staples that will hold it. Too many staples compresses it which defeats the purpose. It is sold in rolls at many fabric and upholstery shops for cheap relatively.
Merely seeing magnified fiberglass made me itchy. I hate that stuff.
I think I'll save the RW for my acoustic panel needs and shop for some natural cotton.
A big thanks for everyone's helpful insights.
Fiberglass is carcinogenic? Try reading this: https://insulation.org/io/articles/...from-fiberglass-building-insulation-products/
The hazard of fiberglass, wood fiber, cellulose, rock wool, asbestos, and every other friable [evil] fiber is the same. They are inert. They don't directly harm you in any way.
What happens is the fibers can get trapped in your lungs, and your immune system detects foreign material and attempts to remove the fibers. But these fibers can get stuck in your lungs, so they can't be removed. When that happens, the immune response ends up essentiall plugging parts of your lungs, reducing lung capacity a tiny amount. If you are exposed to high concentrations of these fibers for a long time, you may develop "asbestosis" many years after the exposure. Like 20 years later.
Modern fiberglass insulation, specifically blown insulation, is different than it was in the past, and now it is miles ahead of rockwool. It produces less airborn fibers, and it is soft, not prickly. I find rockwook particularly unpleasant to work with! I have had several jobs doing insulation work, so I may have more experience than the average person?
I've been reading about the superiority of rockwool for as long as I've been interested in audio; it was the magical material I couldn't have. But recently I discovered that my local store now sells it, so I bought some to do acoustic treatment. When I cut the bag open I was rudely reminded of unpleasant memories of crawling through old house attics, blinded by clouds of fibers floating in the air. It's prickly, and creates a tremendous amount of airborn fibers! Not fun. Far worse than modern fiberglass insulation. No comparison!
I think a lot of the anti-fiberglass sentiment going around may be caused by people who were working with mineral wool, but falsely assumed it was fiberglass.
I've had Owens Corning 700-series product in my professional life and personal environment for something like 48 years, and smoked cigarettes for 20 of those. Anecdotal, of course -- misleading maybe, but maybe not. Use gloves and a mask when handling; cover with a double layer of felt, or spray a 'normal' layer of Kilz, or similar using a Wagner Power Painter; mount it where it will provide the desired absorption and don't worry about it.
Solves plenty of problems, both inside mid/sub cabinets and on an assortment of performance space surfaces.
Cheers
Solves plenty of problems, both inside mid/sub cabinets and on an assortment of performance space surfaces.
Cheers
We had the blow in insulation put in our attack less than two years ago. I wonder how that fluff would perform in speaker boxes. Maybe I might try some inside old cotton pillow slips, to contain it.
Good idea ^
I have thin stainless steel piano wire. I'm going to weave it right through pin holes drilled in the back of the frames to keep the wool neatly in place.
After reading I think its a good idea to fully wrap the stuff up like a big fluffy present in some kind of fabric. Then gently pack it in within its frame.
I have thin stainless steel piano wire. I'm going to weave it right through pin holes drilled in the back of the frames to keep the wool neatly in place.
After reading I think its a good idea to fully wrap the stuff up like a big fluffy present in some kind of fabric. Then gently pack it in within its frame.
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A speaker will have sound waves moving around its insides, and can put fine dust in the area through ports.
And bear in mind the Johnson baby powder issue, costly for them, and they have shut down that business line entirely.
It was brought about (among others) by a lady who was a life long user of the stuff.
As noted above, keep the layers of whatever is used covered properly, I think more safe materials are available as options.
And yes, I was not aware that there was a version of fiberglass that was safe. Thanks for telling me.
Also, I have no connection or interest in Johnson.
And bear in mind the Johnson baby powder issue, costly for them, and they have shut down that business line entirely.
It was brought about (among others) by a lady who was a life long user of the stuff.
As noted above, keep the layers of whatever is used covered properly, I think more safe materials are available as options.
And yes, I was not aware that there was a version of fiberglass that was safe. Thanks for telling me.
Also, I have no connection or interest in Johnson.
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NarishBrd thanks for heads up. The intended speakers are sealed. I probably will never use it inside ported systems.
Also BTW J&J still produce/sell the baby powder here. They all hit reset by claiming its now a safe derivative hmmmm. I guess we will get closer to the truth of their latest public relations fluffing in say, ten maybe fifteen years?
Also BTW J&J still produce/sell the baby powder here. They all hit reset by claiming its now a safe derivative hmmmm. I guess we will get closer to the truth of their latest public relations fluffing in say, ten maybe fifteen years?
Wool , cotton, poly the common hair structures that work.
Poly batten as mentioned incredibly common for furniture, pillows, toy stuff animals
Quilts and blankets. And marketed for HiFi with 3x price markup for many years by brand name
Poly Stuff
Fiberglass is horrible and itchy for sure. still works rather well.
But not suggested since ported will push it out and be able to breath
the fibers. And is gross to handle.
Rock Wool, Mineral Wool, Slag Wool the "cool new" home product for "magical"
speakers. Is home insulation meeting burn rate standards. Manufactured
with formaldehyde or various synthetic formaldehyde. Or any lovely burn
rate carcinogenetic chemical that comes to mind.
Before synthetic hair fibers and batten sheets.
Loose Cotton and Wool held in place with cheese cloth or wide open woven fabric
like " Sheer" cloth for draperies.
Actually When looking at old Altec or Jenson cabinets. Seems it would be really
fun to bring back traditional loose wool and cheese cloth/sheer cloth.
And if anyone even ripped out very old carpet padding, basically that.
Instead of cheese cloth net, used synthetic nylon net to hold together wool
pads
Poly batten as mentioned incredibly common for furniture, pillows, toy stuff animals
Quilts and blankets. And marketed for HiFi with 3x price markup for many years by brand name
Poly Stuff
Fiberglass is horrible and itchy for sure. still works rather well.
But not suggested since ported will push it out and be able to breath
the fibers. And is gross to handle.
Rock Wool, Mineral Wool, Slag Wool the "cool new" home product for "magical"
speakers. Is home insulation meeting burn rate standards. Manufactured
with formaldehyde or various synthetic formaldehyde. Or any lovely burn
rate carcinogenetic chemical that comes to mind.
Before synthetic hair fibers and batten sheets.
Loose Cotton and Wool held in place with cheese cloth or wide open woven fabric
like " Sheer" cloth for draperies.
Actually When looking at old Altec or Jenson cabinets. Seems it would be really
fun to bring back traditional loose wool and cheese cloth/sheer cloth.
And if anyone even ripped out very old carpet padding, basically that.
Instead of cheese cloth net, used synthetic nylon net to hold together wool
pads
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I'm wondering if steel wool could work - available in a range of fine/coarse, has more acoustic mass I guess? One issue would be it needs to be kept away from the wiring, otherwise an ignition/fire hazard, so perhaps bagged up or behind a layer of lighter outer fibres?