@aux/ miller
I was going to do a 4” thick PVC frame with recycled cotton baffle insulation. Initially thinking that a closed back might be better at least with airflow and sometimes I get water down my chimney when it rains. I ordered some burlap fabric to cover. I do think maybe open back may work to allow some of those low frequencies to pass. I guess like Miller says maybe trial and error. I could always cover later.
I was going to do a 4” thick PVC frame with recycled cotton baffle insulation. Initially thinking that a closed back might be better at least with airflow and sometimes I get water down my chimney when it rains. I ordered some burlap fabric to cover. I do think maybe open back may work to allow some of those low frequencies to pass. I guess like Miller says maybe trial and error. I could always cover later.