Speaker wadding on eBay

[walpurgis]

I've seen a possibly useful speaker damping material on eBay. Monacor 75% sheeps wool and 25% polyester mix sheets. Sheeps wool is a useful damping medium. I'm ordering some myself. Its eBay listing No. 3000715136687 from seller dappletoft.

[electric beach]

Geoff, I was recently looking around and saw this too. I made the mistake of buying cheaper and the material was hard to the touch and very inefficient. I decided to try 100% washed wool (also on ebay) and although I've only just started experimenting, I can say it's really efficient - a small quantity made a dramatic difference and I'll only need about 25% of the volume I expected. It's quite clumpy though and have to be sure to break it up; I dare say the Monacor stuff would be more uniform in it's effect.

[walpurgis]

Did you know that B&W did extensive research into various fibres years ago and concluded that long haired teezed pure wool was best for bass damping.

[electric beach]

Well, trying the washed wool directly was a mistake, too dense to allow enough air flow. I spent a bit of time teasing, seperating and fluffing up the wool and it's much better. It's still very efficient in that you don't need as much as synthetic damping and the end result is tonally much better.

I pulled the wool apart by hand first to get it loosened up then used a pet grooming comb (cat/dog) and just kept working at it until I got a fuffy mass with 95% of the knots and tangles removed.

Considering the cost difference of prepared material I'll stick with this in future. It's a bit of a faff but sonically worth it and not a terrible job as far as HiFi chores go - I'd rather be doing this then twisting and weaving bloody bits of wire :lol:


Although... is that me or has a sheep crapped in here?..... :scratch:

[walpurgis]

The reason wool and presumably other animal hair works, is that at the microscopic level the individual hairs have rough surfaces which makes them abrade against each other under vibration thereby soaking up sound energy.

Synthetic fibres are generally smooth and far less effective at absorbing energy, although any damping is better than none in most cases.

Speaker parts specialists can supply loose ready teezed long fibre wool.

One last little point, if you use ported cabinets it may be worth putting fine net across the back of the bass port to stop moths getting in. They eat wool!

[electric beach]

I'm grooming my long haired cats and I'm thinkin'.... :eyebrows:





One kitten per cabinet should do it :eek:

http://theartofsound.net/forum/picture.php?albumid=99&pictureid=954

[Alex_UK]

:lol: That should get your system purring!

[electric beach]

Well it worked OK Alex, tempted them in with a handful of Dreamies. Took a bit of burning in with a few hours of Michael Bubble at a decent volume and the added high frequencies seem to have stopped now. Can't quite get used to that smell though :lol:

[walpurgis]

The wadding in question seems rather good actually. I'm going to buy some more!

[Reid Malenfant]

Sorry to tell you but rockwool is better at damping than long hair sheeps wool ;)

I know simply because I have experimented with both. In a sealed box stuffed with either long haired wool or teased out rockwool, the lowest ultimate driver resonance occured with the rockwool.

Thus the rockwool gave the best damping by fooling the driver into thinking it was in a bigger enclosure, or if you like, the best damping :)

It's also cheap & even better, it's fireproof :D

[walpurgis]

The wool and synthetic sheet is going to be used to damp standing waves rather than pack cabinets. Wool is rather good used for this purpose. I had it's ability demonstrated to me very persuasively.

[AlfaGTV]

If you are experimenting, you may find that IKEA bed comforter/quilts may be a cheap and efficient alternative!
:)

[awkwardbydesign]

Did you know that B&W did extensive research into various fibres years ago and concluded that long haired teezed pure wool was best for bass damping.
So did A.R. Bailey http://documents.jordan-usa.com/Famous-Articles/Bailey-1972-Transmission-Line-Loudspeaker-Enclosure.pdf
I use carding combs to tease out the wool.https://encrypted-tbn3.google.com/images?q=tbn:ANd9GcTUG6RurN144MB7VclIZUA_qXchnjQ-SELmXiIuA2nWgXM-rupNrQ

[awkwardbydesign]

If you are experimenting, you may find that IKEA bed comforter/quilts may be a cheap and efficient alternative!
:)
Trouble with Ikea is escaping from the shop! :eek: I refuse to go there now.

[wiicrackpot]

Following my homebuilt speaker purchase and reading this thread, i was hoping to do it on the cheap and purchased some cheap felt mat from ebay,
received the item today and it's rubbish, so i'd like to warn anybody looking to do it on the cheap steer clear of this stuff,
it just feel like stuffing swept up from factory floor and put through a press to condense it together, needless to say it fell apart in my hands,
moral of the story is listen to Geoff and buy the right stuff. :(

http://www.ebay.co.uk/itm/330559082284?ssPageName=STRK:MEWNX:IT&_trksid=p3984.m1497.l2648#ht_1836wt_961

[Reid Malenfant]

Looks very similar to the stuff used on the inside of the Yamaha NS1000M monitor, along with other damping material ;)

Though it certainly doesn't fall to bits in your hands :scratch:

[wiicrackpot]

Mark,looked good in the listing and spec sounded good but a nightmare to work with, it ripped when i unfolded it, should have got this stuff instead.

http://www.ebay.co.uk/itm/Car-underfelt-soundproofing-sound-deadening-underlay-LB-/180579062315?pt=UK_CarsParts_Vehicles_CarParts_SM&hash=item2a0b59d22b#ht_2009wt_1194

[cooky]

Cold water tank insulation kit from Wicks about a fiver.
2" Fibre glass but when sprayed with hairspray it's fine.
Good enough for JBL, good enough for me!

Cooky

[wiicrackpot]

Frank,

I will take that onboard thanks, it'll come in handy if and when i get my big speaker build project running (GPA 604-8H-III),
always like your post on big speaker builds whenever i come across them and i am a big speaker fan. :)

[cooky]

Hi Andy,

I am also a fan of Duvet damping, it comes already covered in white cotton so is really easy to staple into enclosures and again you can line a pair of large enclosures for under a tenner and in under 10 minutes.

[wiicrackpot]

You know Frank, i actually looked into it (ikea site) and didn't see anything suitable, think i saw that sometime in the past.

[cooky]

You know Frank, i actually looked into it (ikea site) and didn't see anything suitable, think i saw that sometime in the past.

ASDA!

[awkwardbydesign]

Cold water tank insulation kit from Wicks about a fiver.
2" Fibre glass but when sprayed with hairspray it's fine.
Good enough for JBL, good enough for me!

Cooky
The normal practice is to spray fire-retarder on flammable material, not the other way round!

[cooky]

The normal practice is to spray fire-retarder on flammable material, not the other way round!

LOL, tbh if a naked flame can reach the wadding the house has already gone up in smoke or you have a very peculiar listening position:lol:

[ToTo Man]

Sorry to dredge up an old thread but I'm looking to buy some decent damping material to put inside my (currently empty) Celestion Ditton 66 loudspeaker cabinets. (They came with the original foam slabs missing unfortunately). I'd like to go the natural route and use lambswool. I see Wilmslow Audio sell a 75% lambswool / 25% polyester roll, but I'm thinking raw/unprocessed lambswool might be cheaper and more effective? Any links to suitable products would be most appreciated! :)

[iscm]

I am thinking that there may not be one ideal damping material and that
one may just want to dampen the speaker walls, break up reflections, or dampen the box.
It may be that in some speakers there is only a real need to take out some upper bass coloration in which case some light polyester may work possibly together with some wall damping.

In my large B&W DM70's they came with total filling of fiberglass and no damping for the walls except for a bolt to tension from front to the back.
I have now removed some of the filling, using laundry wash bags to help keep what is left central.
The use of floor mats (the natural sort 3/4 inch thick and rubber backed) stuck to the inside rear has been useful to prevent a resonance of the rear panel and reduce reflected upper bass inside of the cabinet. I may try more on the rest of the larger sections.
I used spray carpet adhesive to great effect here.

One thing I know is that large speakers are much harder to get right, but I hope my experience will help others.

In the future I may try long fiber wool to replace the fiberglass, but I am having problems sourcing it in the UK.
How much better than fiberglass is it? :D

[alphaGT]

Polyester fill can be purchased really cheap at sewing shops, or where sewing notions are sold. The same exact stuff they use in speakers for ten times the price. I don’t see why fiberglass would be a better stuffing? Maybe they get it cheaper? You can pack polyester in as dense as you like, or not so dense. I’ve used it in a few speaker projects with great success. Spray on rubber undercoating for cars, works great on the insides of the cabinet, to deaden the panels. Wool is much denser than polyester or fiberglass, so you can just use it against the walls, or pull it apart to puff it up, best thing about it is no itchy fiberglass up your nose!

Russell

[iscm]

Polyester fill can be purchased really cheap at sewing shops. The same exact stuff they use in speakers for ten times the price. I don’t see why fiberglass would be a better stuffing?
Spray on rubber undercoating for cars, works great on the insides of the cabinet, to deaden the panels. Wool is much denser than polyester or fiberglass, so you can just use it against the walls, or pull it apart to puff it up, best thing about it is no itchy fiberglass up your nose!
Russell

I think that the reason to choose different materials is that wool and fiberglass work on lower frequencies.
Depending on the speaker and box design the requirements can be different.
Wool is said to work well because of its complex fibers, but fiberglass does not get moths.

It may be that polyester is fine for some speakers, but my large DM70's for instance require something that will dampen bass frequencies.

[diviy]

My speakers are Ditton 15xr and have foam in them just wondering if this wadding stuff would make much of a differance ?

[walpurgis]

My speakers are Ditton 15xr and have foam in them just wondering if this wadding stuff would make much of a differance ?

I thought the damping in the Ditton 15xr was about right, adding more may kill the life in them.



Speaking generally, rockwool/fibreglass are horrible unfriendly to use materials and best avoided. They are not even particularly good at damping and used to be chosen by manufacturers for cheapness.

Synthetic fibres have smoother surfaces than organic ones, so do not work against each other as well to dissipate energy. BAF (bonded acrylic fibre) is more effective though.

Long fibre wool is effective at lower frequencies, but poly foam is better at higher frequencies. 'shoddy', a sheet material made from natural and synthetic waste fibre and sometimes sold as carpet underlay can be useful too, as an 'all round' damping material.

Take your pick according to purpose.

[iscm]

If I'm not mistaken, stuffing a cabinet with absorbent material will change the effective box volume (it acts as if it was a larger box), so a reflex design will have all its box/port tuning parameters changed and thrown off alignment. Ideally the stuffing and the port tuning need to be designed together, or at least the port tuning needs to adjusted after stuffing.

The Ditton 15 is not exactly a reflex design, but used an auxiliary bass radiator (ABR) which is tuned to the box volume and bass/mid, so I agree that it is not a good idea to alter the box parameters too much.

Rather than changing stuffing, I may consider an internal brace or two between the front and back walls could help the boxes structural rigidity. These could start from between the tweeter and min/bass to rear and between the mid/bass and ABR to rear.
If they were cut so as to be a tight fit and then glued in place, they could be beneficial without changing the box volume too much.

With speakers of this vintage, I would also think about replacing the capacitors in the crossover. :D

[walpurgis]

The Ditton 15 is not exactly a reflex design, but used an auxiliary bass radiator (ABR)

An ABR system is a reflex type. The passive radiator does a similar job to a port.

[diviy]

With speakers of this vintage, I would also think about replacing the capacitors in the crossover.
I have allready done that and fitted better speaker binding posts

[iscm]

I have allready done that and fitted better speaker binding posts

Then the only thing left is bracing and possibly wiring (nothing too fancy).
Did you change away from any electrolytic's that there may have been?

I seem to remember that the Ditton 15 tweeter was often used together with a Coles supertweeter in other speaker designs.

Sorry if this is all a bit off topic for this thread, but as discussed before, it may not be advisable to change the wadding too much in these particular speakers.
The same applies to all tuned (Reflex, Transmission Line and ABR) designs.

I suppose that it may be worthwhile using some bituminous damping in the inside panels as used in car deadening kits.
In my B&W DM70's I glued door mats to the inside of rear panels to great effect, but I think that due to their thickness they would not be appropriate for the Dittons.

Good luck and let us know how you get on.