Dynamat Extreme or Damplifier Pro, what would you run?

[Slow Ride 10+ year member]

my question has to do with coverage. with a mass loading type damper why does everyone cover every square inch with multiple layers? Wouldn't you want to just add enough mass to lower the resonant frequency below 20hz and then add a layer of decoupling foam and then a layer of mass loaded vinyl to finish? Seems like a lot of additional weight without much gain. A panel is not going to vibrate as much with a bend in it. Also, how much do you guys spend on this stuff? I have a regular cab truck that is my daily driver. I have a very small system to install. So far I have 2 price quotes for just materials that are over $500.

 

[Rudy 10+ year member]

my question has to do with coverage. with a mass loading type damper why does everyone cover every square inch with multiple layers? Wouldn't you want to just add enough mass to lower the resonant frequency below 20hz and then add a layer of decoupling foam and then a layer of mass loaded vinyl to finish? Seems like a lot of additional weight without much gain. A panel is not going to vibrate as much with a bend in it. Also, how much do you guys spend on this stuff? I have a regular cab truck that is my daily driver. I have a very small system to install. So far I have 2 price quotes for just materials that are over $500.

You wouldn't want to cover every square inch with multiple layers UNLESS you were trying to lower the RF below 20 Hz, in which case you will be astonished by how much mass (layers in this case) you'd need to add. Both of the products being discussed are constrained layer viscoelastic dampers that work by converting vibration to heat.

Adding mass is only a viable strategy when the object is being excited by a single frequency or very narrow band of frequencies and you need to move its RF out of that range. This doesn't have much application in aftermarket automotive vibration damping and is completely impractical when you are trying to get the average vehicle panel below the audible range.