Mortite/Rope Caulk for Cabinet Deadening

[sdclc126]

Hello All,

I did a search first - I've read about using rope caulk/Mortite to damp woofer frames, and one post talked about using strips of it to partially line a speaker enclosure, so...

I was wondering if anyone has ever used this stuff to completely line the inside of a speaker cabinet to damp resonances?
Would it work? Is it practical? Cost effective? Would you still need to address standing waves, etc. with stuffing?

I'm also wondering if there are other substances out there that might be used to do this - like the kind of clay that doesn't harden - what is that, some kind of artist's clay?

I guess anything with moisture in it would probably be a bad idea, but anything that remains soft and pliable without leaching moisture might be a possivility.

Well, just thinking out loud here, so please feel free to think out loud back!

[Pano]

An interesting idea!
I'll admit I've been thinking about it, but have not tried it.

Rope caulk does work very well on the back of horns, metal or plastic, as well as woofer frames. I'm glad I found the stuff, used to use messy tar on the back of horns.

But would it work on the walls of cabinets? It would certainly add mass and dampen resonances, just as it does elsewhere. But wouldn't it reflect sound a bit?

Let's hope some folks who know more about it will chime in.

[Cal Weldon]

I think it will do the job but perhaps be less than cost effective. You'd need a huge amount of those packages of strips. Also, you will need a way to fasten it as it has poor adhesive qualities and will fall off the sides and top. It's great for seating a big driver though.

Do you have a supply of it?

[sdclc126]

No Cal I don't have a supply - I'm wondering if it can be purchased in bulk perhaps.

And yes cost could be a big factor, so I'm wondering if there are alternatives - like clays etc.

I saw a photo somewhere once (it may have been on this site but I don't remember the source) where a guy had put huge amounts of something that looked like clay on his woofers - it looked pliable as it had molding marks all over it - he obviously applied it by hand and formed it as he went - like molding clay.

Maybe there are other putties out there like rope caulk that are cheaper and come in larger quantities. Back to Home Depot I go!

Also going to do a search on the web - might be able to find something at builders's supplies or hobby/arts/craft supplies. If I come up with anything I'll re-post.

[sdclc126]

P.S. -

As far as adhesion goes perhaps the cabinet could be built as a sandwich, with the caulk in between the layers, and ribs could be used to form a framework between the layers and provide further strengthening/damping.

Ooooooh! Lotsa work this would be, but it might make an awesomely dead cabinet.

[kevinkr]

Going to this amount of work to sandwich a cabinet sounds like the right place to use... sand.

Mortite is not forever stuff in my experience - it hardens over time, and it is pretty reflective above some arbitrary frequency. Best used for temporarily sealing leaks. It sticks ok to paint, will stain some materials, probably doesn't matter here though.

[LightwaveDude]

I've heard about people using blu-tac on the back of drivers to add weight and dampen resonances. From what I've seen, it looks like a bunch of blue artists clay.

[Pano]

The rope caulk from Ace Hardware is very sticky stuff. No problem getting to stay on horns, drivers, box corners, that sort of thing. Don't know if it will last forever, but I doubt my speakers will, either.

I agree with Kevin. If you are going to the touble to double wall, use sand.

[nunayafb]

I've heard about people using blu-tac on the back of drivers to add weight and dampen resonances. From what I've seen, it looks like a bunch of blue artists clay.

Definately not for art, it is actually an adhesive clay. If it gets dirty it loses its stickiness(just like tape), but when fresh can be used for immobilizing parts on a desk, hanging light objects etc. But I would not trust it to stay attached to vibrating walls indefinately.

They make sheets of material exactly for the application in question, i dont remember if they are self adhesive or if they glue on like veneer. These sheets however are actually designed for reducing panel resonance, I belive they're the same ones use on newer cars.
I dont remember the post but it is somewhere on this site, the effectiveness/availibility/cost are discussed.

[DigitalJunkie]

I've never lined an enclosure with it,that might be a bit hard to do,a single 2mm strip at a time!

I have used it to dampen baskets and around the magnets and stuff on subwoofers,and it does work quite well for that!
I've also used silicone in a pinch,it works well too!

I also usually use it to seal the speaker to the box,just a bead around the rim. Works well,is non-hardening,and is easy to remove later,if you want to swap drivers.