Hi!
To make the octave analysis of frequency domain data you have to pass in your time domain data to the Octave Analysis VIs. The time domain data will allow you to window the signal using the correct values.
The Sound and Vibration toolkit has several examples that show how to do this. You can find them under Help>>Find Examples and then browsing to Toolkits and Modules>>Sound and Vibration. This directory has Traditional DAQ and NI-DAQmx examples as well as Octave and Third Octave analysis.
You can also look for other examples using the Example Code Library.
Good Luck,
Tica
