Multi-Sub Optimizer Tutorial (page 10)

Measurement Groups

So far, you've seen how to plot measurements, filter channel frequency responses and filtered measurements. But one piece of the puzzle is still missing: how do you plot the combined output of multiple subs and main speakers at a given listening position? This is done using measurement groups. A measurement group is a collection of filtered measurements that are added together (properly taking phase into account) to form a single combined response. To plot the combined outputs of Sub 1, Sub 2, Sub 3, Sub 4 and main speakers at each of the four listening positions, you'll need to define four measurement groups, one for each listening position. Measurement groups are also used by the automatic optimizer. If you define these four measurement groups, the optimizer will adjust the filter parameters to optimize the frequency response at each listening position.

To define a measurement group, activate the Config View tab at the lower left of the main window. Scroll down to the bottom, where you'll see a folder icon named Measurement Groups. Right-click on this icon and choose Add Measurement Group from the context menu. For the first group, you'll choose all the measurements from position 1 as shown below.

Defining a measurement group
Figure 19. Defining a measurement group

Click OK. In the Config View, a new icon is created under Measurement Groups called Measurement Group 1. This name isn't very descriptive, but you can easily change it. Select Measurement Group 1 and press F2. This allows editing the name in place. Since position 1 is the main listening position, call it MLP as shown below.

First measurement group defined
Figure 20. First measurement group defined

Create three more measurement groups, choosing all measurements in position 2 for the first, position 3 for the second and position 4 for the third. Rename these groups Pos 2, Pos 3 and Pos 4 respectively. The result should look as below.

All measurement groups defined
Figure 21. All measurement groups defined