Best products for baffle material s ?

PTSS, I haven't read every post here, but I think your
premise, that a less resonant cabinet is better, is simplistic
and flawed. Every material, regardless of density and weight,
has a resonant frequency. Companies like Spendor and Harbeth,
who both produce excellent products, have opted to go with a
thinner, more resonant box in order to shift the resonant
frequencies into the range they wished them to be. This takes
time, sophisticated measuring equipment and (most of all) a
clear idea of what the maker wants the finished products to
be. Your approach of just building a non-resonant cabinet is
nothing but trial and error and the misguided theory that
heavy cabinets are automatically better. Just to be clear,
there are many companies using heavy cabinets with great
success, but again, the process is not haphazard. At least it
shouldn't be. My advice - if you don't like what you have,
sell them and buy something you like. Unless off course, you
just want to screw around with a project, which if fine. It's
your stuff and you can do whatever you want with it. Good
luck.

Vapor1 - You misinterpreted my post. I am saying that the OP
believes that if he builds a heavy enclosure, it will
automatically be superior to the one he has now, which he
believes vibrates. He may well end up preferring what he has
now. I am saying that cabinet design is much more complex
that gluing together some heavy pieces of material. And
Vapor1, if you're saying that Harbeth and Spendor speakers are
built on misguided theories, well - I guess you have the right
to your opinion.