HOW TO MAKE PARAGAMI DIY SOUND ABSORBER / ACOUSTIC 3D WALL ART

I'm not using standard construction foam; instead, it's FLEXIBLE ACOUSTIC FOAM, which has distinct properties and structure.

The manufacturer claims in the datasheet that the foam offers a sound insulation rating (according to EN ISO 717-1) of 62 dB.

This foam is open-cell and flexible, meaning it can be compressed and later it returns to its original shape. It allows airflow.
Additionally, when cut, it becomes visibly porous, which enhances its sound absorption and helps reduce reverberation.
In that sense, it behaves similarly to the common polyurethane pyramid-shaped acoustic foam panels.

There are several brands, but I’ve tested a few, and they all seem pretty similar. Just grab a
low-expansion ACOUSTIC/FLEXIBLE foam from your local hardware store or go for the cheapest one online. Low-expansion foam is important because you want small, tight bubbles.

Filling the blocks with foam takes a little practice. It expands over time and can sometimes spill over the edges. It’s no big deal if that happens; the surface dries first, so it doesn’t fully stick and is easy to clean up later.

Filling the blocks with foam takes a little practice. It expands over time and can sometimes spill over the edges. Fill around 60%. It’s no big deal if that happens; the surface dries first, so it doesn’t fully stick and is easy to clean up later.

Once the foam has set, it’s time to trim the excess. I designed the blocks with flat tops, so just grab a knife and carefully cut away the surplus foam. It’s easy to do!

Tip: Be patient and let the foam fully harden—overnight if possible. Even if it feels dry on the outside, the center might still be expanding. If you cut it too soon, not only will your knife get messy, but the foam might continue expanding, creating large bubbles. You’ll end up with an uneven surface, so it’s best to wait.