Loose sand would be better. The damping occurs through absorption of vibration and dissipation as movement of sand. What you are proposing is just adding mass and minimal at that. Sand has plenty of mass. Clean it first or buy clean indoor sand(yes it exists) Microspheres will not help at all.
Sand is excellent at that. Ofcourse only if you can contain it somewhere, somehow. Unfortunately with a microphone stand that's not possible because it still has to be adjustable. The speaker stand would have to be built new from scratch with a sandwich material.
What exactly do you want to achieve by that? Is it a resonance of the stands or the reflections of it you try to eliminate? If you want to reduce the latter, that's very easy, you can use open pore acoustic foam and simply tape or glue it to the surfaces.
What exactly do you want to achieve by that? Is it a resonance of the stands or the reflections of it you try to eliminate? If you want to reduce the latter, that's very easy, you can use open pore acoustic foam and simply tape or glue it to the surfaces.
Well he suggested suspending the glass bead in silicone or latex, I would think that would indeed damp a fair bit. Even just filling with plain silicone/latex would go a long way.
For the mic stands.. on the larger outer tube I would use heat shrink tubing, slide it over the tube and shrink it with a heat gun, trim off excess. Inside or smaller extension tube.. I'd use an expansion foam (Great Foam or similar) to fill the inside of this tube. I'd suggest using a swab to clean the tube so the foam will stick. You may need to use an extension on the foam can nozzle to make sure you get the foam throughout the tube.
Wear gloves while working with the foam. The foam will not stick to saran wrap or similar plastic wraps.
For speaker stands I would need to see a pic, just too many kinds.
stled
Wear gloves while working with the foam. The foam will not stick to saran wrap or similar plastic wraps.
For speaker stands I would need to see a pic, just too many kinds.
stled
I'm looking to damp the rods of the mic stand (except the lower which as noted needs room for adjustment-I've attached asphalt pads to the outside before though), and the internal cavity of some cheap lighweight speaker stands. I'll be using sorbothane feet between the stand and speaker, and rubber feet between stand and floor.
I've used sand before and it seemed to work well, but always seemed to leak out. So this time I want something that stays put.
I considered the type of foam you spray for insulation, but I don't get the feeling that stuff actually damps well. It is fairly rigid when cured.
I've used sand before and it seemed to work well, but always seemed to leak out. So this time I want something that stays put.
I considered the type of foam you spray for insulation, but I don't get the feeling that stuff actually damps well. It is fairly rigid when cured.
Brandon, I've used the minimal expansion foam in many applications and it works for me. In the 90's we built competition sound cars and used it by the case lot.
If the speaker stands are tubular construction it should work for them as well.
If I can help feel free to PM me and I'll give you a call.
Ed
If the speaker stands are tubular construction it should work for them as well.
If I can help feel free to PM me and I'll give you a call.
Ed
It's a Dow product they have a large selection but I mostly used the minimum expanding foam in the orange can listed for gaps and cracks.
Dow GREAT STUFF™
Ed
Dow GREAT STUFF™
Ed
Just cheap silicone caulk should do most of what you want. The thinner the wall of the stand, the better.
If you want something that damp.s better you'll need a thin (2-3mm) compliant surface (silicone caulk) next to metal you want to damp (..inside of stand), with a loose HEAVY material filling, (lead shot), the rest of the volume. Microspheres are counter productive as a filler because of the low weight.
If you are going to use expanding foam then invest in the gun dispenser format. The stuff is great (sorry) for a lot of things, even treating air leaks around doors and windows (who knew?) but seriously the ordinary big box version is not fun to use at all.
There is the dynamat option for damping, or the budget alternative which is sold at home improvement boxes as gutter/metal roofing patch, consisting of sticky asphalt with heavy aluminum foil affixed. I have found it effective on steel speaker baskets to quiet the ringing they cannot not do.
I used "OneTime" microsphere filler as speaker damping on a small woofer and it was very effective, actually too much so. It did remain stuck to the cone and dust cap, which was a concern. Modern acrylics are better than we want to think they are sometimes.
"Heavy aluminum foil"...did I write that? I meant thick.
There is the dynamat option for damping, or the budget alternative which is sold at home improvement boxes as gutter/metal roofing patch, consisting of sticky asphalt with heavy aluminum foil affixed. I have found it effective on steel speaker baskets to quiet the ringing they cannot not do.
I used "OneTime" microsphere filler as speaker damping on a small woofer and it was very effective, actually too much so. It did remain stuck to the cone and dust cap, which was a concern. Modern acrylics are better than we want to think they are sometimes.
"Heavy aluminum foil"...did I write that? I meant thick.
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Is mass the critical property? Discussions on this forum regarding CLD and microspheres describe friction of the vibrating microspheres as the thing that dampens vibration. From that I would assume you want to maximize surface area of the spheres (as a whole) contacting the carrier adhesive and each other, so the smallest diameter spheres?
weight is the critical property - specifically as it acts on the damper (the compliant interface between what you want damped and that heavy filler).
Best would be a bar of lead for each damped surface (glued to that surface but free to move "back and forth"). But "barring" (ouch) that, lead shot should do it, and I don't think the size of it really matters that much (I'm assuming something small here) depending on the thickness of the damping layer (and how much the shot sinks into that layer). You could probably improve upon it by creating a soft roll of fabric or foam in the center (like a 1/2" "dowel" that extends from the bottom to the top) of the stand so that the shot has a bit more movement to react to the compliant damper.
On of the more critical things is the thickness of the damping layer - it needs to be thin (but not to thin), like only a couple of mm's.
Ex. .062" thick sheet
E-A-R ISODAMP Damping Materials from Rathbun – Vibration Damping Rolls, Vinyl Sheets
Best would be a bar of lead for each damped surface (glued to that surface but free to move "back and forth"). But "barring" (ouch) that, lead shot should do it, and I don't think the size of it really matters that much (I'm assuming something small here) depending on the thickness of the damping layer (and how much the shot sinks into that layer). You could probably improve upon it by creating a soft roll of fabric or foam in the center (like a 1/2" "dowel" that extends from the bottom to the top) of the stand so that the shot has a bit more movement to react to the compliant damper.
On of the more critical things is the thickness of the damping layer - it needs to be thin (but not to thin), like only a couple of mm's.
Ex. .062" thick sheet
E-A-R ISODAMP Damping Materials from Rathbun – Vibration Damping Rolls, Vinyl Sheets
So If I'm understanding correctly, you would disagree with these statements by Geddes:
"Basically it is the filler that yields good damping - lots of small particles rubbing against one another."
"A CLD panel is far better damped than a solid panel of equivalent thickness - basically its NOT "mass damping" because there is no such thing. Mass is mass and damping is damping - different things that should not be confused with one another."
-it depends on the context. Lots of small particles rubbing against each other IS the damping effect - creating a loss.
What I'm suggesting is maximising a loss layer through the application of reactive weight.
The CLD marketing is just going against other products that are mostly about the damping layer, having very little reactive weight to that damping layer. With these type of products spot damping is better and they strongly depend on large thin panels that need damping (..like a car door). Having a smaller and thicker panel that is terminated on most of its sides is MUCH harder to substantivly damp.
Mass dampers are of course real (and weight is just the gravitational effect on mass). It's of course easier to judge the property of the reactive "weight" via it's measured weight (..you'll rarely get a measure of mass for any given object).
What I'm suggesting is maximising a loss layer through the application of reactive weight.
The CLD marketing is just going against other products that are mostly about the damping layer, having very little reactive weight to that damping layer. With these type of products spot damping is better and they strongly depend on large thin panels that need damping (..like a car door). Having a smaller and thicker panel that is terminated on most of its sides is MUCH harder to substantivly damp.
Mass dampers are of course real (and weight is just the gravitational effect on mass). It's of course easier to judge the property of the reactive "weight" via it's measured weight (..you'll rarely get a measure of mass for any given object).
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