I have tried the Solens and they are ok but they seem to compress the dynamics.
Really? I found the opposite, with all of them, when used in my ESL xovers, and even in my Plasma tweeter xovers, especially I found the SILVER METALLIZED POLYPROPYLENE to be vey good, but everything has to be perfect to handle these babies, because they’re so fast and clean.
Which ones did you try?, as there are quite a few models (8 I believe) that can do the job inside a speaker xover.
Cheers George