My current build is a pair of 3-way floor-standers in sealed boxes. My habit is to design boxes with minimal parallel faces and to brace the living daylights out of them. My vertical bracing is usually 3/4" (18mm) Baltic birch 2" wide and my horizontal braces are full-width with varying cut-out patterns. I typically end up with a lattice pattern of bracing on the exterior panels with individual rectangular spaces varying from 4" to 6" (100mm to 150mm) on a side. This lends itself to the use of 2" thick rigid glassfibre panels, which are easy to cut and friction-fit neatly into the latticework I've created.
This also fits my Unibox model for the woofer which uses "Walls covered" for the damping. I more typically build ported boxes, so I'd be interested to know how literally the builders of sealed boxes interpret this. The problem I have is that my box design is such that access to adjust the amount of glassfibre will be extremely limited once I've bonded the baffle in place. By removing the 10" woofer, I will be able to get at the glass behind the woofer and in the bottom of the box, but they're the places where it's needed most. I may be able to pick at some of the pieces nearby, but to limited extent.
I'm inclined to fully line the walls on the basis that whatever I can get at will be easier to remove than to fit once the box is sealed up. Does anyone have any more penetrating insight?
Thanks!
This also fits my Unibox model for the woofer which uses "Walls covered" for the damping. I more typically build ported boxes, so I'd be interested to know how literally the builders of sealed boxes interpret this. The problem I have is that my box design is such that access to adjust the amount of glassfibre will be extremely limited once I've bonded the baffle in place. By removing the 10" woofer, I will be able to get at the glass behind the woofer and in the bottom of the box, but they're the places where it's needed most. I may be able to pick at some of the pieces nearby, but to limited extent.
I'm inclined to fully line the walls on the basis that whatever I can get at will be easier to remove than to fit once the box is sealed up. Does anyone have any more penetrating insight?
Thanks!
It is sealed so you can just fill the space with folded over
poly batten sheets.
Absorption is more effective in the middle of enclosure
which is usually not done or achievable with ported.
poly batten sheets.
Absorption is more effective in the middle of enclosure
which is usually not done or achievable with ported.
Pictures of the bracing.
I have seen rigid fibreglass used as damping by some i respect but it is hard for me to get excited about it.
Sealed, i would fill with REALLY well teased acoustastuff or similar. (if you are close i have a whack of it spare)
dave
I have seen rigid fibreglass used as damping by some i respect but it is hard for me to get excited about it.
Sealed, i would fill with REALLY well teased acoustastuff or similar. (if you are close i have a whack of it spare)
dave
Yes, a pic would have been useful:
The space in the upper centre is the TM enclosure, and the space below is for the woofer. The space behind and below the woofer will be easy to adjust later, but the rest will be severely constrained by the vertical bracing. I currently have the TM box, the back walls, and the bottom fully lined with 2" glass. I'm ready to start attaching the baffle, but I could loosely thread some poly batting up through the bracing on each side (per WhiteDragon's comment) first. I'm still contemplating adding glass on the baffle side of the braces up each side, although I suspect that it's a case of diminishing returns.
I may be taking Unibox too literally when it says "Walls covered" and I wonder why it offers that as an option when conventional wisdom is to stuff a sealed box.
The space in the upper centre is the TM enclosure, and the space below is for the woofer. The space behind and below the woofer will be easy to adjust later, but the rest will be severely constrained by the vertical bracing. I currently have the TM box, the back walls, and the bottom fully lined with 2" glass. I'm ready to start attaching the baffle, but I could loosely thread some poly batting up through the bracing on each side (per WhiteDragon's comment) first. I'm still contemplating adding glass on the baffle side of the braces up each side, although I suspect that it's a case of diminishing returns.
I may be taking Unibox too literally when it says "Walls covered" and I wonder why it offers that as an option when conventional wisdom is to stuff a sealed box.
Looks a lot like what Chris did for these.
MDF?
And no brace for the back of the woofer to the box?
Default damping for a sealed box is line it, buit stuffing, AFAIC, will further reduce standing waves being pklaced in a much more useful place.
Lined is what you do in a reflex. In a sealed boc it will slightly lower th eQ, usually a good thing.
dave
MDF?
And no brace for the back of the woofer to the box?
Default damping for a sealed box is line it, buit stuffing, AFAIC, will further reduce standing waves being pklaced in a much more useful place.
Lined is what you do in a reflex. In a sealed boc it will slightly lower th eQ, usually a good thing.
dave
Very nice. My design is based on the Sonus Faber Stradivari (but not as tall). Thus it will be deeper than Chris' design and not symmetrical.
All birch ply (now almost prohibitively expensive) except for the baffle which will be laminated MDF. No woofer rear brace.
All birch ply (now almost prohibitively expensive) except for the baffle which will be laminated MDF. No woofer rear brace.
Ours was inspired by the SF Ellipsa ;^)
We did figure, even at the price for premium ply its cost was swaped by everythign else — almost all the MDF we could use could be had for free.,
dave
We did figure, even at the price for premium ply its cost was swaped by everythign else — almost all the MDF we could use could be had for free.,
dave