I have made some small, but thick, bass traps for in between speakers, next to center speaker.
I have used rigid fibreglass for first 3', then behind that is a a piece of Earthwool 33kg/m3 5' piece.
I do not want to suck out too much HF, thus I have place kraft paper and cling film around them. Is that okay? I have thick cling film, bin liner(thin plastic), and kraft paper. Which should I use? For these small 30cm x 30cm ones I used the above, but I have more to make. I figured the plastic that rolls, slabs come in is twice as thick as cling film, thus both paper and cling film together would be okay.
Any feedback would be appreciated, cheers.