Bass trap materials

I have been reading a lot of information on room treatments. I would like to add bass traps and some side wall materials. I would like to build them myself and have been looking online for help. My question is the materials to use for the bass traps. Most of the diy projects show them using fiberglass insulation for the sound absorption material. My thought was that I would use wool insulation bates instead thinking it is a better option for the application.
Would like to hear from the the family out there to your thoughts and any suggestions on a better material and your own experience if you have made your own traps.