Unsound - everything matters, and there may be some effects from the forward parts. The cross struts are 1/4" diameter round bar, and not in the path of any drivers. The forward side verticals are 1/2x1/2" MDF, but so far off axis that they present a diamond profile more so than a flat surface. In developing those grilles, we couldn't measure or hear any deleterious effects (although they are hypothetically present.) The fabric itself does add resistance as frequency increases. We voiced for flat with that fabric in the sound path.
That grille cloth was the most transparent we could find. Present cloth is even more transparent.
Beginning with the CS2, those frames went away, except for the CS5.
Our first CNC mill in 1985 allowed us to machine the more sophisticated solutions beginning with the CS2.2. Later, such as in the 2.4, the 1/16" die-cut steel frame virtually eliminates the frame's geometric advantages.
That grille cloth was the most transparent we could find. Present cloth is even more transparent.
Beginning with the CS2, those frames went away, except for the CS5.
Our first CNC mill in 1985 allowed us to machine the more sophisticated solutions beginning with the CS2.2. Later, such as in the 2.4, the 1/16" die-cut steel frame virtually eliminates the frame's geometric advantages.