If you’re looking for simplistic old school acoustic treatment you can do every bit as good as GIK only faster and for a tiny fraction of the cost stretching whatever fabric you like over Owens Corning acoustic panel. In fact if you look at their website they have the exact same OC panels. If paying $1k for $50 worth of room treatment is worth it to avoid having to learn how to use a sheetrock knife, go for it.
GIK is simplistic old school treatment. Next generation and so much more effective you can hardly believe it are Synergistic Research HFT. They make these in different versions designed to go on walls, ceiling, and speakers. Unlike the panels that do very little really, and nothing that like someone already said can be done with furniture (carpet, etc) these things are insanely effective in improving imaging, extension, detail, dynamics, essentially making your speakers, and walls even, disappear.
I’ve done panels, traps, corner tunes, you name it, going back to the 90’s. Actually my 1973 teenage bedroom had egg cartons, functionally identical to GIK just not as pretty. Compared to HFT that stuff is stone age. People I guess are slow to catch on. So you get a lot of advice from people stuck in the 1950’s. Go figure. Free 30 day trial. Which don’t worry, you will not be sending them back.
