https://youtu.be/-8AKV1ER8vI
We used Rockwool fiber panels called "Terræn Batts - erhverv" in Denmark - somewhat similar to the Owens Corning mentioned in many of the DIY sites. (not exactly the same, but the closest we could find, and good enough).
The frames are made of very cheap un finished 25mm times 45mm plywood, put tighter with small metal corners.
The Cloth is so called "bed linen" type cloth (breathable and somewhat stretchy)
The video fails to show that we put a small piece of wood on the bottom of the frame to keep the fiber boards from sliding down, duo to the stretchyness of the cloth - remember this if you use this type of cloth.
All in all it took us about 30minutes pr frame of "non stressing" work, and cost about 200.- DKR equivalent of about 30USD pr frame.
We made 14 in all and put them up in our studio (electronic music studio, not recording studio)
