I think you might not fully understand the abilities of viscoelastic coatings. In addition to reducing stucture borne noise, they also have a very good mass loading effect. The only issue with them is that a decoupler is not in place, so the results are not as good as a true barrier. These coatings however, will reduce more aiborne noise than constraint layer dampers (when applied at similar thicknesses) . As I stated in my previous post, the difference between the vinyl formulation and the coatings formulation is just a few small changes in resin type (an a couple small addatives) the cured elastomeric coatings are very similar to the vinyl barriers. Barriers however do not exhibit the same viscoelastic nature as the coatings do. Applying a coating on the hood is a great way to pick up extra surface area when you are trying to nail down the last few trouble spots. As you drive, the engine noise travels through your fireswall, in to the cabin. This is where most of the engine noise that we hear comes from. The rest comes either from under the car, or over the car. Some sound waves go through the hood, which then enter through our windshield and ceiling, or under the car through the floor pan. Anythin you put between the source of the noise, and your ears will, to some degree reduce noise. Some things are obviously better than others which is why using the most efficient product for the desired goals is always ideal. That being said, Spectrum is a very cabale vibration damper and to some degree (a larger degree than other products) will reduce airborne noise as well. There is simply no way around this ////M5 I konw you are going to chime in, and try to tear my logic apart. I know your motives. I am sure you want to help people on this forum. I have read your other threads, and though I do not always agree your negative tone and methods, I can appreciate your blunt honesty, and I do know that you know your shit. But please, if you are going to continue to follow me around this forum, and try to evoke a response by talking trash about me, even in threads that I am not posting in, I would encoureage you to stop. No only does it make me feel uncomfortable coming to this forum, ( a forum I am a vendor on) but I am sure you are driving away other members of this forum as well. Several have spoken to me about how you make them feel uncomfortable as well. Don't expect me to jump in to any further debate with you, as I already konw how it will end up. ANT