Edwyn Acoustics Bass Trap 1.2m tall ( Stackable ) available in Black or Beige – Absorption and Diffusion. Recommended to be placed in the corners of the room $599 - Simply Hifi
DIY HOW TO BUILD EASY BASS TRAPS FOR YOUR EPIC HOME STUDIO! - YouTube
DIY Acoustics: Building Your Own Tube Traps — SonicScoop