The IE‑45's Average Mode offers very powerful features that allow a user to create continuous or triggered averages of various types, as well as select the type of average (power average or arithmetic average) that best suits your measurement.
In the RTA mode, tap on the "Average‑A" stylus button. The default condition for the stylus button below the Average button is "Cont", which indicates that you will be starting with a continuous average. When you tap the Average‑A button, the button text changes to "Count = X" where "X" is the number of samples so far collected. You will see the sample number increment as the number of automatically collected data samples increases.
A blue line will immediately form on the RTA screen, which is the graphic representation of the average that is being collected. The more samples collected, the slower this average display will change as short duration acoustic events are encountered. The data sample collection can be paused and resumed by tapping Pause/Resume stylus button. The average curve can be captured into a scratch pad memory by tapping any one of 9 scratch pad memory buttons.
Tapping the "Cont" stylus button will switch it to "Trigger" where the data samples for averaging are taken only when the user manually triggers a sample by pressing the "Add" stylus button.
Arithmetic v.s. Power Averaging
The IE‑45 performs two types of averaging. The Arithmetic Average (Average‑A) does straight arithmetic averaging which is best used when you are viewing the RTA screen while doing active equalization or other dynamic spectral adjustments. Power Average (Average‑P) is most useful in measurements where the total power is more important, such as transmission loss. Switching from Average‑A to Average‑P is done by tapping the "File/Preferences" menu.