3
Frequency resolution
Third -octave bands
Models SE and DL
Third -octave bands
Each octave band can be divided into three adjacent bands called third-
octave band. Because of the logarithmic relationship between adjacent
bands, the center frequencies of third-octave bands differ from each other by
26%. For example, the center frequency of the next third-octave band above
the 1000 Hz third-octave band is at 1260 Hz. Figure 1-3 is similar to Figure 1-
2 but shows the thirty-three third-octave bands in relation to the instrument’s
bandwidth.
Figure 1-3: Third Octave bands
Naming bands
Bands are conventionally named for their center frequencies in accordance
with acoustical industry standards. Table 1-1 identifies the SoundPro SE or
DL models that have octave and third-octave bands option with their exact
center frequencies and their corresponding standardized names.
L
evel
Summary of Contents for SP-DL-1
Page 1: ...3M Personal Safety Division 3MTM SoundPro SE DL SeriesSound Level Meters SoundProUser Manual ...
Page 13: ...xii Table of Contents Models SE and DL This page left blank intentionally ...
Page 35: ...22 Turning off Navigating Models SE and DL This page left blank intentionally ...
Page 69: ...56 Communications GPS Models SE and DL This page left blank intentionally ...
Page 89: ...76 Back erasing Stopping a session Models SE and DL This page left blank intentionally ...
Page 137: ...AC DC output DC output 124 Models SE and DL This page left blank intentionally ...
Page 149: ...Appendix A 136 Models SE and DL Block Diagram for SoundPro ...
Page 161: ...Appendix B 148 Models SE and DL This page left blank intentionally ...
