Porous and resonant absorbers combine to achieve broad frequency coverage.

Evidence

It is possible to combine the effects of porous and resonant absorbers to form wideband absorbers. A typical construction is shown in Figure 6.48 and its performance is shown in Figure 6.49. As with all absorbers using rock-wool or fiberglass one must take precautions to prevent the egress of irritating fibers from the absorber into the space being treated. — David Howard, Jamie Angus, coustics and Psychoacoustics, 2109

Categorization

• XREF: connects to: Wide-band membrane absorbers shrink non-environment rooms to fifteen square meters — David Howard, Jamie Angus, coustics and Psychoacoustics, 2295