How to stuff speakers with polyfill

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Hello, I just made a pair of speaker cabinets for my PS95 Dayton audio full range drivers which are going to be used with a sub as a 2.1 system. I am having trouble figuring how to stuff them. I understand that the best way to stuff speakers is to try and see what sounds best, but I would like some guidelines. The internal volume is 0.1ft3(2.8 liters) and I am using this insulation Buying a Sonofil - Black? | SoundImports - SoundImports and Buying a Monacor MDM-4? | SoundImports - SoundImports

Am I supposed to just layer it in the inside walls or try to expand it and stuff it inside? How much should I putt? How close to the driver?

Any tips?
 
For your application, I would choose the Monacor 60% cotton, 40% polyester mix, but the other seems OK too.

For your sealed enclosure I would form the damping sheet into a loose cylindrical roll whose dimensions suit the enclosure.

Leave some 'breathing space' directly behind the driver by ensuring that the driver's magnet won't unduly compress the damping once the driver is installed.
 
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Batting is in sheet form, commonly 100% polyester, typically made for making quilts and such. Its form works well for lining the enclosure walls. It can also work well for stuffing, as Galu illustrates, or by using very thick sheets and layering them.

Poly-fil is the same stuff as 100% polyester batting, but in loose form like in a stuffed animal or pillow. That works well if you intend to stuff the enclosure fully, or to the point that it begins to affect the thermal properties of the system. If you go this route, again be sure to leave a little room between the driver and filling.
 

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guidelines to stuffing a box...my first impulse is to say "dinner and drinks, first"

it's a hot potato topic...enough to make a difference without adversely effecting response or overall subjective volume is what i would say in the absence of a measurement system.
 
I'd assume there's a sweet spot between;

1. Effectively damping / suppressing the reflection from the rear wall of the cabinet.
2. Significantly reducing the cabinet volume because it's so crammed full of stuffing.

So I'd think you'd want enough so the box doesnt sound like a tank or drum, but neither jammed full. Perhaps start with it empty and using a small speaker (music playing thru), listen to it echo. Then add stuffing until its hollowness calms down.

This is all just a guess. Good Luck!
 
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I too think there is a 'sweet spot' i.e. an optimum amount of stuffing.

For a closed box design the design often relies on loose volume stuffing to moderate the cabinet volume to produce a specific acoustic response. The cabinet volume is effectively increased by some 5 to 10%.
I personally favour attaching a thick layer of dense absorbent to the rear cabinet wall in order to prevent/reduce direct reflections from emerging through the speaker cone. The rest of the enclosure I fill loosely with a less dense absorbent,

I also agree that the amount of absorbent is best established by ear!
 
frugal-phile™
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I personally favour attaching a thick layer of dense absorbent to the rear cabinet wall in order to prevent/reduce direct reflections from emerging through the speaker cone. The rest of the enclosure I fill loosely with a less dense absorbent,=

I sort of do that. I typically line the box near the driver with 12mm cotton felt, and then use well damped acoustastuff or similar. This for sealed or TLs, BR you just line the enclosure, althou the stuff linked to would be good for mounting on a holey/driver brace in the middle of the cabinet.

dave
 
frugal-phile™
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Fill the cabs and leave off the back. You'll like the sound in the room much much more. The box serves no useful purpose.

With a driver like this, if you follow this recipe you will have NO bass.

This is the kind of box i have suggested often for higher Q drivers (ie AN 15” or Vistaon B200), and for some midranges. It is not an original idea. Search “boffle”.

dave
 
For your application, I would choose the Monacor 60% cotton, 40% polyester mix.
That looks like a good product. Not sure I've seen it before. Mind you, I've been a rock wool guy for many years now. I don't think it can be beat on the price/performance scale.
For your sealed enclosure I would form the damping sheet into a loose cylindrical roll whose dimensions suit the enclosure.
Simple yet effective. Maybe a little on the top and bottom as well. No need to get too technical is there?
 
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