For dynamat to work (i.e. dampen vibrations and block noise) YOU must treat the thing that is causing the sonic problem you want to improve...

if the door sheet metal is being shaken by the back-wave of the speaker then the damping ability of dynamat on the sheet metal will reduce the resonance factor of the door thus improving frequency response (improving mid-bass for instance)

BUT if you treat inconsequential items you will have minimal performance... my point is you might have treated the wrong part of your door...

 

I think i would have been better off applying the dynamat to the inner door cavity "behind" the magnet. At least this will provide some dampening. As mentioned i have only enough dynamat to cover a 12" diameter area in the inner shell directly behind the speakers magnet. Do you think i will still see a noticable difference, or should i go buy another dynamat door kit?

 

Assuming there is a problem (and remember throwing money or material at something cant fix a non existent problem) I would recommend putting a full layer on as much of the door as you can get to. If you need to go to a local dealer and they SHOULD be able to sell you scraps

These type of products help reduce:
1. system resonances (may seem or may actually be louder)
2. noise intrusion into the car or music being heard from outside the car (this is how I judge effectiveness by how much sound escapes the car)
3. the cars affect on the music (smoother tonal balance)

 

Ok,

First of all, why dont you save some money and instead of buying expensive Dynamat use relatively cheaper FatMat from the Canadian vendor located in Oakville, ON. They can ship as well. I dont want to mislead you, as I've never used Dynamat per se, but FatMat worked for me just fine.

Second, I've covered the outter part of the door (side facing you) 99% surface with the exception of 1% where the lock mechanism is located. Take a look at the install pics. By covering it tight both in/out you should gain some decent results...

Good Luck !

 

Everybodys experience will be different. If you are dealing with speakers screwed directly to a metal panel and then you add dynamat to that panel, yes there may be a very noticable improvement - both because of the added mass and also due to better sealing of the driver to the door. If you already are using stiff heavy mounts (like your 3/4" rings) for the driver, then your results may not be as dramatic.