Cotton Wool in the back tweeter's chamber

[diypass]

i want modify the absorbing material of the back chamber of my tweeter.
my question is what material is preferred:

- cotton wool: cotton wool balls
- lambs wool: Lambs Wool Speaker Stuffing (500g) | KJF Audio

which has the particular properties for stuffing the tweeter back chamber ?

😉

 

[Moondog55]

More information needed.What tweeter for a start and what is the volume of the back chamber.
I think I used woollen felt in the back chamber of the Vifa I did a while ago but I know I used a small amount of carded wool in the hollow pole piece as per this link.
Lamb's Wool Tweak - Vifa PL27TG-35

 

[diypass]

the tweeter is seas 27tdc, i don't know the chamber volume, sorry

 

[Moondog55]

It's a reasonable HF driver why do you feel the need to tweak it?
I was under the impression it already had the optimum damping in the rear chamber and a foam plug in the pole piece

 

[Indiglo]

This may be of interest, from Speaker Design - Pole-Piece Vent Felt Tweak - Seas T25C003 tweeter

 

[OscarS]

you should try Mundorf Angel Hair.

 

[wolf_teeth]

When I recently modded my b-stock RST28F4 tweeters, I firmly inserted a cotton ball in the pole, and tightly packed Ultratouch denim insulation into the cup. The improvement from the out of spec readings I achieved was not small. Of course, your mileage may vary.

Later,
Wolf

 

[Galu]

With regard to your question on which has the particular properties required for the task:

Conventional absorbers depend on their fibre and porous structure for their performance.

Cotton fibres have very similar sound absorption properties to fibreglass. The most effective natural absorbers, like cotton, consist of the smallest and most compactable fibres.

Wool is only slightly less effective at absorbing sound than cotton, possibly because its fibres are bigger and so harder to compact to the same degree.

 

[diypass]

you should try Mundorf Angel Hair.

i abhor mundorf product 😉

 

[diypass]

When I recently modded my b-stock RST28F4 tweeters, I firmly inserted a cotton ball in the pole, and tightly packed Ultratouch denim insulation into the cup. The improvement from the out of spec readings I achieved was not small. Of course, your mileage may vary.

Later,
Wolf

good!, have you some measurements to view this, i'm very curious 🙂
also was differences in the timbre ?

 

[wiseoldtech]

I've saved old polyester filled bed pillows for their stuffing.
Used it for all improvements concerning speaker enclosures.
Just rip the pillow open and use that - it works beautifully as an effective absorber for internal reflections.
And.... it's cheap.

 

[Galu]

you should try Mundorf Angel Hair.

So that's where I went wrong! 😀

 

[GM]

I've used 'blocks' of 1-2" thick acoustic fiberglass insulation: Type 703 & Type 705 Series Fiberglas™ Insulation Boards - Owens Corning Insulation

GM

 

[phivates]

Does that Angel Hair have a break-in specification?

 

[wolf_teeth]

good!, have you some measurements to view this, i'm very curious 🙂
also was differences in the timbre ?

I have not done but quasi infinite-baffle measurements using felt and my carpeted floor. They are not in the completed destination as yet. I don't even know what midbass to put with them yet.

Here is the thread I started on the matter:
MWAF contestants, B-Stock RST28F-4 info... -

Techtalk Speaker Building, Audio, Video Discussion Forum

Later,
Wolf

 

[diypass]

thank you