Tests
2
Effect of Hole Diameter
Rw range
7dB
spread 0 dB
Highest Rw
7dB
SM 1.6 mm Round (11.0%)
Largest ΔRw vs first
±0dB
SM 2.38 mm Round (23.0%)
Sound reduction index
R′ from the 2270, re-referenced to the 0.9216 m² specimen area (−0.35 dB). Grey lines: reference bounds.
Single-number ratings
Open in explorer| Varies | Test | Rw | C | Ctr | ΔRw vs first | ΔRw vs open | Mean R | |
|---|---|---|---|---|---|---|---|---|
| SM 1.6 mm Round (11.0%) | Project041 | 7 | 0 | −1 | ref. | +7 | 6.0 | |
| SM 2.38 mm Round (23.0%) | Project044 | 7 | 0 | −1 | ±0 | +7 | 6.0 |
Rw, C and Ctr per ISO 717-1 over 100–3150 Hz. ΔRw fits the reference curve to the band-by-band difference curve, which is not the same number as subtracting two separately rounded Rw values. Mean R is the arithmetic mean over the 16 rating bands.