Displaying Order Levels in a Graph

This section enables you to get a more detailed view of the dominant orders. You can compare several orders using evolution vs. time, or evolution vs. RPM. and create datasets for Car Sound Simulator.

Note: To change the maximal order display in this graph, change the value of the field Highest order for order view in File > Preferences > Order analysis. For more information on order analysis preferences, see General Settings.
Note: Order export is only possible from Time/order or RPM/order representations.

To Display Order Levels in Graph:

Prerequisites: You need to detect orders.
  1. Right-click the representation then choose Rpm/Order or Time/order display.
  2. Right-click the representation then choose Order analysis...


  3. In the Export orders window, type the rank of the needed orders respecting the selection syntax.

    • If you need a reference curve, enable Overall level vs time.

      Note: Occasionally, the level of an individual order curve may be higher than the overall level curve (which is theoretically impossible). The reason is that two different methods are used to calculate the level of an order and the overall level. Details about order level estimation can be found under Theory of Order Analysis. Overall level is calculated using the customized level vs time method explained in Parameters Overview, using a Hann window of length 100 ms, and a time step of 10 ms.

    • In the Order analysis resolution, type a percentage to adjust the width around the order.

    1. Click OK to validate.

The order levels curves are displayed in a time-domain window.

The order levels are displayed in the original linear unit of the temporal signal versus time. When the original unit of the temporal signal is Pa, the order levels may be displayed in Pa vs. time, dB SPL vs. time, or dB(A) vs. time. See Changing the Ordinate Unit of the Order Levels Graph. When the initial signal's unit is not Pa, the display unit cannot be changed from the signal's original unit.

Tip: To switch scale to RPM abscissa, right-click the order level graph then select Rpm/level display.