I have a pair of Vienna Acoustics speakers, that have a sealed chamber in the bottom to fill with sand. I recall (20+ years ago now, tho) that I noted it helped deepen the bass on the speakers, I assume by damping panel resonance. It is not a giant speaker tho, only 8"Wx10"Dx34"H, with 1" HDF walls.
Has anyone tried sand in a similar capacity? Does it really do anything?
I am building a new speaker, using 11-ply 3/4" baltic birch ply for the front, back, and internal supports. The sides will be curved, and I am using 3 layers of overlapping 3/8" birch wiggle wood (fun stuff!) for a 1 1/8" total side width.
I am wondering if I should build in a similar sand compartment in the new speakers. I haven't seen any other designs leverage this, so perhaps is it only a small effect?
Has anyone tried sand in a similar capacity? Does it really do anything?
I am building a new speaker, using 11-ply 3/4" baltic birch ply for the front, back, and internal supports. The sides will be curved, and I am using 3 layers of overlapping 3/8" birch wiggle wood (fun stuff!) for a 1 1/8" total side width.
I am wondering if I should build in a similar sand compartment in the new speakers. I haven't seen any other designs leverage this, so perhaps is it only a small effect?
Adding sand isn't going to change the bandwidth, but it could help make the bass more articulate, by reducing panel vibrations as you say.
jeff
A lot of sand in these:
The sand does a good job of damping and makes the box a bit more immune to moving due to reactive forces.
The really nice stands we used, were massively improved by filling th emetal colums wioth sand.
dave
The sand does a good job of damping and makes the box a bit more immune to moving due to reactive forces.
The really nice stands we used, were massively improved by filling th emetal colums wioth sand.
dave
Some years ago, a friend built box within box cabinets for 15" drivers with a gap between the layers filled with sand on all six sides. Every side but the front has a lower and upper cork - not vertically aligned - sanded flush , indicating that the sand filled cavities were separated by inter box connection strips. I'd guess diagonal.
The boxes weigh a lot, I'd guess between two and three hundred pounds. They give that kind of bass you can feel in the air but not in the floor.
The boxes weigh a lot, I'd guess between two and three hundred pounds. They give that kind of bass you can feel in the air but not in the floor.
Thanks all! I will definitely make a compartment for sand in the new speakers as well. I think I will shoot for a 8"H compartment at the base.
Those old Viennas were filled by flipping them upside down with a plug on the bottom. I dont love that option. I'd rather have the sand sealed in. Either a plug in the top board for the compartment, or maybe I pour epoxy over that top board to really seal it up.
Picked up the plywood, starting on the frame today.
Those old Viennas were filled by flipping them upside down with a plug on the bottom. I dont love that option. I'd rather have the sand sealed in. Either a plug in the top board for the compartment, or maybe I pour epoxy over that top board to really seal it up.
Picked up the plywood, starting on the frame today.
Toofill an empty space?
In the FOnken167 i posted pictures of we wanted floorstanders, so we extended the sides to the floor. Then we had an empty space. We filed with sand, but at least 1 build had an 8” helper woofer in the bottom bit.
dave
In the FOnken167 i posted pictures of we wanted floorstanders, so we extended the sides to the floor. Then we had an empty space. We filed with sand, but at least 1 build had an 8” helper woofer in the bottom bit.
dave
Yeah, I get that, but it kinda sounds like the OP is going to include an empty space (for sand) which isn't strictly necessary. Maybe I'm missing something.
jeff
Don't do the same mistake I did with my first trial with sand, and that was to not remove all moist from the sand I used.
So make sure it's extremely dry, otherwize it will start to smell quite bad after a while.
Bake it in your owen over night, and make sure there is no small bugs or eggs from bugs.
So make sure it's extremely dry, otherwize it will start to smell quite bad after a while.
Bake it in your owen over night, and make sure there is no small bugs or eggs from bugs.
I took the bag of playground sand and spread it out on a big tarp in the driveway on a hot sunny dry day and shifted the sand around around over the course of the afternoon.
dave
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Yes, I think I made 5 or 6 speaker projects with sand filled cabinet walls before giving up. Too messy. Better to glue several layers of MDF, braze properly and use the right amount of dampening material in the cabinet.
But if you have the possibility to use sand in a given cabinet I would recommend it.
It will help to reduce the resonant peaks the cabinet creates.
easiest way to do it is using paper boxes for sending CD's.
put it together seal with wood glue.
make a little "door" on one side and fill it with fine dry sand. close it with wood glue.
you can glue these sand filled cardboard boxes with wood glue into the box.
dry fine sand is sold for birds
put it together seal with wood glue.
make a little "door" on one side and fill it with fine dry sand. close it with wood glue.
you can glue these sand filled cardboard boxes with wood glue into the box.
dry fine sand is sold for birds
Like Dave, I’ve put sand chambers in my tall thin cabinets to weigh them down and as a side effect, damp some of the resonances. I make a sealed compartment in the base so the sand can’t move around the box or become a home for bugs. I use sanitized play sand which is finer than construction sand and has no bugs or mold in it.
good is also constrained layer damping with silicone glued tiles inside the box.
because i have access to cheap work and affordable marble i use marble for boxes.
because i have access to cheap work and affordable marble i use marble for boxes.
If you have some ceramic tiles you can glue them on the inside. Extremely stiff material that is a perfect constrain material. Also add some mass which is good!
I like those, care to share more about these speakers? Drivers, design, plans?A lot of sand in these:
dave
Old design for FE167. Given it is a big standpoint with sides that reach the floor, any standmount could be morphed into similar.
This one has a helper woofer instead of sand.
dave
This one has a helper woofer instead of sand.
dave