My system so far has made a massive difference and I'm only half way through it. I am however almost as tight as a Scotsman. Obviously not in the same league as a Yorkshire Tyke but careful with my spends.
If you go the Dynamat rout be prepared to be a little disappointed. That is unless you double it up and cover 99.9% of everything which is going to cost a remortgage. Not bad for a car but I feel a trattor is a little too much for it.
I set out to 1, reduce the noise entering the vehicule and 2, stop the noise that does bouncing around the cab so I hear it twice and thrice over.
Your going to have to cover everything. If you leave 10% uncovered it wont mean the noise will reduce by 90%. Thick EVA foam is belting at reducing noise against its cost. The lock together dance/yoga mat is very good indeed if fitted properly and by proper I mean completely. It needs to be bonded to the steel with high temp contact spray adhesive and superglued at the joins and edges. Done this way 10mm is more than enough. I even cut circles out of it for access to screws and nuts but put the circles back in with a dab of low tack adhesive. A little can be cut out of the back to allow room for bolt heads ect.
Mostly its down to quality of fitting. In areas that have several defense layers including plywood lining,flashband (to reduce drumming), foam backed vinyl, I have used 10mm camping bed mat. Its better at bending to shapes as its a little lighter and is foil backed to aid insulation.
Once the noise is in the cab with you (and your going to get some) your going to need something to absorb it quickly. Carpet, foam, crushed velvet curtains............. Whatever dings your dong, but that sound has to be deadened.
Take the ceiling in my series diesel. It was the first to get the treatment;
Noise reduction first
Strips of 100mm cheap unbranded flashband layed randomly on central flat areas with gaps between strips. Every metal panel will at some point match its resonance to vibrations from the engine. Thats when it goes off like a guitar string, just not as pretty. Flashband reduces this.
10mm EVA foil backed camping mat HMP (brush on, its stronger) contact glued over the top with foil inwards.
Then absorbing layers
18mm upholsterers scrim foam HMP spray contact glued over the top with the scrim surface inward.
Man made faux shammy leather vinyl spray glued on top to finish. You could use any head lining type absorbent finish.
Just this made a noticeable difference
The glass alone will let noise in but any bare metal, even if not on the outside, will transfer noise and needs covering, even behind the dash.
My footwells will have a 3mm layer of solid rubber matting glued to the metal. Then EVA foam. Then a sheet of 4mm plywood to regain rigidity, then a bespoke carpet and finally a molded rubber foot mat for protection and ease of cleaning. Tactfully purchased and all done by my own fair hand the whole thing will be half the price of a self adhesive, expensively marketed and pretty useless, fancy named underfelt...........
Ear defenders are a cheaper option
