System 831 - Octave Band Analyzer
The Model 831 can perform just 1/1 or
1/3 octave real-time frequency spectra
measurements or they can both be
measured simultaneously. These spectra
will be made using a user-selected
frequency weighting (A, C or Z). The
averaging time is the same as that
selected for the sound level level
measurements (Fast, Slow or Impulse).
Spectral data is displayed on both the
Live and Overall Pages, but only the
Overall Data can be stored.
Live Page
From the Live Page, the graphic shows
the instantaneous SPL value for all
frequencies and the bar to the far right
shows the summation value for the entire
frequency band. The value corresponding
to the cursor position is displayed
numerically beneath the graph.
Overall Page
From the Overall Page, the graphic shows
the energy equivalent level calculated
over the measurement time period at each
frequency band and, at the far right,
for the summation of all frequency
bands. The values displayed digitally
beneath the graph represent the
following data for the frequency band at
the cursor position.
• Leq
• Lmax
• Lmin