My Insight seat is more comfortable for me than any chair in our home. Here is why: The seat height was a little lower than I wanted so I purchased high tensile strength metric machine screws (bolts with a hexagonal socket built into their head that accepts a six sided Allen wrench type driver). The front are fairly common but the back 2 are fine threaded and less common. I cut some 5/8 inch thick PVC plate into large washers using about a 1 1/4 inch whole saw in a drill press. The PVC is limestone dust impregnated with a softening temperature of around 400 degrees so it makes a strong, waterproof and stable spacer that accepts black paint nicely.
The back of the seat cover unzips. I took some foam rubber sheeting similar to what you would used under a heavy traffic carpet installation and made a lumbar suppot that I slipped between the zig zag spings and the existing foam. This pushed the lower part of the seat back forward and firmed it up. If I remember correctly I used a little PCB board material between the new foam and the springs to give a broader pressure distribution. I adjusted the fit by sitting in the seat between adjustments. If you do this after a days work in the garden you will get the most definative custom fit.
Et Voila! I soon had the most comfortable seat in the house or any non custom car. This mod is completely invisible, but now everyone here will know my little secret. Sigh. Well, how could I not try to help after your kind words about this group.
:idea: One more note, the fabric that covers the seat is an open weave that breathes and gives nicely. It can however be easily damaged by things catching in it. If you are going to wear pants or jackets with studs, zippers, or Velcro fasteners on the back, you might want to get seat covers.
As for sound damping......shaved beaver fur laminated with layers of lead foil is best. OK, so shoot me for trying some Canadian humour! :roll: If beaver pelts, thick cotton terry towels, or Persian carpets are not on the menu, there are commercial products available. If I recall one is called brown bread or something to that effect. Try using the search function as this has been discussed here at some length. I made up some custom shapped sacs from pool lining felt and stuffed them with small scraps of accoustical felt I had left over from speaker designing. I placed these into some open areas under the back coverings with the idea of damping resonances from the rear speakers I installed. Phew, I've got to set up a personal page with photos soon.
Have fun with your new car.