All Software Features

Octave Analysis

ObserVIEW generates octave bands with an 8th order filter to meet IEC 61260-1 Class 1 filter specifications. It performs filter-based analysis and applies A and C frequency weighting, linear and exponential averaging, and peak hold.

Download Demo All Software Features

What is Octave Analysis?

Octave analysis allows for the subjective evaluation of sound and vibration by grouping the frequencies of an acoustic signal into “bins,” often to reflect how humans perceive the frequency spectrum.

microphone on tripod

First, the software program filters the acoustic signal and measures the sound pressure levels at the output. Then, you can apply averaging and weighting techniques in the frequency domain to correspond to the measurements of your desired evaluation of sound.

Learn More

ObserVIEW Highlights

  • 8th order octave band filter to meet IEC 61260-1 Class 1 filter specifications
  • Filter-based analysis with the option of FFT
  • A and C frequency weighting or none (Z)
  • Linear and exponential averaging
  • No limit on fractional octave bands
  • Configure reference values for each unit category
  • Peak hold and overall RMS traces (SPL for pressure units)
  • Harmonic cursor

Filter-Based Octave Analysis

True octave analysis applies bandpass filters to the frequency range and averages each filter’s output to compute its power. ObserVIEW performs filter-based analysis as it produces more accurate results.

octave analysis filter-based

ObserVIEW can also use FFT data—which measures the frequency content linearly—and assign the energy to the proportional octave. This method is efficient but is only recommended if your computer cannot handle the filtered option.

Supports Any 1/N Fraction

Enter any 1/N fraction that suits your test objectives; ObserVIEW does not have a limit on fractional octave bands. (Note: there is a soft limit at 1/96 for computer performance, but you can override the limit.)

Advanced Graph Functions

The octave band graph supports the advanced graphing capabilities of ObserVIEW, including live analysis, copy & paste, and graph traces.

Peak Hold and Overall RMS

  • Peak hold: displays the maximum amplitude for each bin over the peak hold data range.
  • Overall RMS: displays the total RMS for the integration period using the selected filter (SPL for pressure units).
  • Harmonic cursor: displays the trace values at each harmonic of the base cursor.

octave analysis harmonics

Audio Frequency Spectrum

The audio frequency spectrum is an overlay that represents the range of human hearing. Bass frequencies range from 20 to 250Hz (purple), Mids from 250 to 4kHz (yellow), and Highs from 4k to 20kHz (pink).

audio frequency spectrum

Data Acquisition

Vibration Research’s data acquisition systems offer the functionality to acquire and analyze acoustic signals. All VR hardware includes a BNC input that supports a microphone and is capable of data acquisition.

Product stack with ObserVR1000, VR9500 and VR10500

If your testing lab is already using VR hardware for vibration testing, sound acquisition and analysis is an economical addition.

View Products

How Can We Help You?

Contact Us