Octave Band Analysis

Sound Level Meter with Octave Band Analysis | Model 831C-OB3

831C Sound Level Meter

In many applications, it is important to acquire both the broadband level and spectral content of noise data. With spectral information, the source and content of the measured overall level can be better understood. Constant percentage bandwidth filters (1/1 or 1/3 octave) best approximate human perception to sound. 831C-OB3 Firmware enables simultaneous real time measurement of 1/1 and 1/3 octave Leq, Lmax, Lmin along with all the ANY LEVEL™ broadband parameters. 831-OB3 is compliant with IEC 61260:2001 Class 1 and ANSI S1.11-2004 Class 1 standards and covers the entire frequency range of human hearing: 6.3 Hz to 20 kHz for 1/3 octave bands.

When 831C-OB3 is combined with Time History Logging (831C-LOG) or Automatic Event Detection and Event History (831C-ELA) it is possible to review the frequency content of logged data or specific events.

Highlights

  • Simultaneous 1/1 and 1/3 Octave Filters
  • 1/1 Octave Filters from 8 Hz to 16 kHz
  • 1/3 Octave Filters from 6.3 Hz to 20 kHz
  • IEC 61260 and ANSI S1.11 Compliant
  • 2.5 ms interval available (optional)
  • Leq, Lmin and Lmax computed
  • Spectral Ln

Applications

  • Determine frequency content
  • General purpose noise measurement

Live Octave Band Display

View Octave Band data live on-meter, in G4 LD Utility Software, or the LD Atlas app.

LD-831C-OB3-Octave-Band-Analysis

Graphical Representation of Octave Band Data

With optional Time History firmware (831C-LOG), G4 LD Utility Software displays results graphically. View octave band levels over time as a heat map.

831C-OB3 Specifications
Octave Analysis Parameters
1/1 Octave Filters8 Hz to 16 kHz
1/3 Octave Filters6.3 Hz to 20 kHz
FiltersNone, 1/1 octave, 1/3 octave, or 1/1 and 1/3 octaves
Frequency WeightingA, C, or Z (independent of broadband weighting)
Maximum SpectrumMaximum in each band or Spectrum at broadband Lmax
Spectral Statistics6 percentiles per filter
Octave Band Logging Capability Time History (see 831C-LOG)
Measurement History (see 831C-ELA)
Event History (see 831C-ELA)
Octave Filter Standards
IEC61260 Ed. 2.0 (2014) Class 1
ANSI S1.11-2014 Class 1
Normalized Spectrum
View ModesSPL, Leq, Lmax, or Lmin; absolute or relative
Predefined FiltersA, C, -A, -C
User Defined Filters4 named for 1/1 Octave and 4 for 1/3 Octave bands