All speakers, M80's included, were designed to perform in a specific way by those that designed them. Ian, Alan, and whomever else played a role in designing the M80's knew what they wanted and produced a speaker that met those goals. Their goals.
If your goal is to tweak the sound to your own liking, why they heck shouldn't you? They're your speakers.
I can't imagine that putting in more polyfill would somehow damage the speaker. Good idea to ask Axiom though.
But it's certainly not a permanent change. Maybe it'll change the SQ in a way that you like. Maybe it'll make it worse. Maybe it'll do absolutely nothing. Even if you *think* it helps, then it's a worthwhile improvement for you.
Good luck! Just let the group know what happens. I'm sure there are many who would like to know the outcome of whatever tweaking you do.
