t.akustik Spektrum D20 Diffusor

I puchased the t.akustik Diffusors after having owned 8 pieces of Hofa diffusors, which I felt were underperforming (badly built and adding coloration). The Spectrum D20 is very well built: solid and heavy, not ringing at all, and doing its job much better than the Hofa variant. Do note that the slits are not all 100% straight as in the photos of the perfect sample, but it's still much better than the Hofas. Visuals aside, for the much better performance as well, they are well worth the relatively small extra cost. Note that these panels are 60 x 60, not 50 x 50 like the Hofas, meaning they are even better value for money.