Peerless 830875 in sealed box

[TMHutson]

I am curious to see if you like the sound of your sealed enclosure once it is done.
Andale pues!

[ramiro77]

Believe me, I'm more curious than you Meanwhile I am using cheap aiwa speakers. I want to finish right now these new enclosures.
I am quite sure that work perfectly with subwoofers.
Anyway, I'll measure them when finished. I have to figure out how to make a good measurement below 300hz. I don´t know if I can do that without an anechoic chamber. In that case, you're going to have to believe only in my ears: (

[sreten]

Hi,

Below 300Hz you have to use nearfield measurements and trust the physics.

rgds, sreten.

[ramiro77]

Understood. It is worth making the measurements outdoors? I have a garden in the back of my house, about 30 x 9 meters, no walls in between which could disturb. I never thought of making the measurements there in a day without wind or noise, and pointing the enclosures to the sky, to minimize unwanted reflections due to the floor.

What do you think about this?

[sreten]

Hi, Take a look at Paul Messengers articles on measurement at Stereophile, rgds, sreten.

Nearfield measurements for the bass end can be done indoors with the right gating.

[ramiro77]

Thanks sreten, i´ll take a look at those articles

[ramiro77]

Well, I bought the glass wool. I couldn´t find rock wool. The construction of the boxes will take me some days longer than planned, because I've added some wood details. But I tried for a few minutes a single box, not stuffed inside, and looks promising. Of course, bass is not devastating, but I had the impression that can be used completely without subwoofers. I also try to equalize, increase 4db 50hz, 4db 60Hz 2db at 70hz, and they're pretty much like the bass reflex enclosure. I didn´t notice any excursion problem. Surely with the filling will be much better.

What do you recommend me for filling? Can I use only glass wool on all sides of the box? Or it´s better combinate with polyfill?

[DualTriode]

Hello,
The last set of speakers i stuffed with raw wool from a sheep. The real thing worked well. The idea came from an old Linkwitz paper.
I bought the wool on line from a woman that sells wool from her few sheep to DIY folks that spin their own yarn, pretty cool I thought.
DT
All just for fun!

[ramiro77]

But it´s late DT, i´ve bought glasswool yesterday.
Someone recommended me to use glass wool in the bottom of the box and polyfill in the rest of the walls. But because I bought a lot of glass wool, I wondered if it would be correct to place on all sides and not use polyfill.

[DualTriode]

Originally Posted by ramiro77

But it´s late DT, i´ve bought glasswool yesterday.
Someone recommended me to use glass wool in the bottom of the box and polyfill in the rest of the walls. But because I bought a lot of glass wool, I wondered if it would be correct to place on all sides and not use polyfill.

Hello,
I learn by doing as well.
The way I think of the stuffing is like adding density to the air in the box. Back when i read that the fiber glas should be attached to 3 inside surfaces top, side and back to reduce reflections. Perhaps all 6 inside surfaces. Other boxes are completely filled with soft fluffy stuff. This is increased density fill concept. Some speaker software programs have a blank to fill in for weight of the stuffing added. The idea is that as the box filling air and stuffing has density (weight) that will adsorb heat from the adiabatic compression of the air. On the negative pressure side of the sound wave the stuffing gives the heat back, the oppisit of the heat of compression. The stored energy or heat is the equivalent of added box volume. The stuffing also helps keep the sound inside the box from bouncing around like a ping pong ball.
The short version staple the fiberglass batts to the inside walls and weigh out 6, 8, or 12 Ozs of pillow stuffing into each and see how you like how it sounds.
To answer your question directly, it is all good!
No sheep?
DT
All just for fun!