Is it foam? Then no.
Is it MLV? Then yes.
/End of thread.
Is it MLV? Then yes.
/End of thread.
While you did achieve something by using the CLD (dynamat) to control panel borne vibrations, the foam did absolutely nothing to block sound from coming into your vehicle. Adding a layer of MLV on top of that foam however, would actually do something to reduce noise, assuming the foam you used actually has a good compression resistance rating. And unless you used neoprene foam, I have a feeling your foam's compression rating sucks.Then there is foam (still not home carpet foam), which is Actually For sound deadening. Amazon sells it cheap and it is very easy to use and cut. If you need pics or tips just shoot me a PM. I did my entire car with both dynamat and the edead foam. Rides and sounds like a new car now.
Some well made polyethylene foams can have with good compression recovery too, depending on how they're manufactured.
\begin thread....Is it foam? Then no.
Is it MLV? Then yes.
/End of thread.
Not useless. If it has good density and mass, as metioned it can be very effective. Good luck finding such foam, though.Using foam as a SOUND BARRIER is useless.
On paper, yea. In real world testing you can see fairly respectable NRC figures (even some STC's, too) from like 6# 1/2" composite foam or cotton products.It only blocks frequencies whose wavelengths are at least 1/4 of its thickness, so even with 1/2" foam you will only be blocking frequencies waaaaay above 20khz, or outside the range of human hearing.
I only said MLV because its relatively easy to find, pretty cheap, and somewhat easy to work with. Most people won't bother with making a 'sand glue sandwich' or using lead in their car, and I never said that MLV is the only option out there.\begin thread....
Mass is mass is mass is mass. Did you know mass is mass and that more mass per unit surface area is THE name of the game for sound refraction/blocking? Yea, it's true. No mo MLV dogma, ok? Thanks.
Again, most people won't ever be able to find such dense foam that would make it useful in that application, and as such most foam people actually think of or use actually IS useless. Just because an esoteric version of it exists out there somewhere doesn't mean the average person knows about it, and it definitely isn't what they think of while putting ensolite in their car.Not useless. If it has good density and mass, as metioned it can be very effective. Good luck finding such foam, though.
At some point you are just looking for low cost substitutes for low cost substitutes. MLV was developed to be a low cost substitute for lead. Most of the alternatives I've seen have enough deficiencies to not be worth the effort. If you can string something together out of material that is free to you, you may come out ahead of the game. Walking the aisles at Home Depot probably won't pay off It's sort of like looking for a cheaper version of cubic zirconia - you're already 99% of the way there.I only said MLV because its relatively easy to find, pretty cheap, and somewhat easy to work with. Most people won't bother with making a 'sand glue sandwich' or using lead in their car, and I never said that MLV is the only option out there.
Right, rule out the idea that thin foam will be any kind of barrier or do much vibration damping. It's good for two things - attenuating high frequencies and isolating adjacent objects or surfaces. It's possible that the OP's carpet padding might have some use - subject to all of the caveats already listed, but only as a substitute for foam, the least important and least expensive ingredient in the mix.Again, most people won't ever be able to find such dense foam that would make it useful in that application, and as such most foam people actually think of or use actually IS useless. Just because an esoteric version of it exists out there somewhere doesn't mean the average person knows about it, and it definitely isn't what they think of while putting ensolite in their car.
That's pretty much what I was trying to say, that using thin foam specifically as a noise barrier won't get you anywhere. I never said it doesn't attenuate very high frequencies, or that it doesn't do an admirable job of isolation surfaces from vibrations. In fact, I use to to keep panels from vibrating against one another and it works quite well.Right, rule out the idea that thin foam will be any kind of barrier or do much vibration damping. It's good for two things - attenuating high frequencies and isolating adjacent objects or surfaces. It's possible that the OP's carpet padding might have some use - subject to all of the caveats already listed, but only as a substitute for foam, the least important and least expensive ingredient in the mix.