Figure 4.22 - Copies with two Arrays
That is the easiest way to get a matrix style set of copies.
4.4.1 Arrays and reference objects
Besides using values to control an Array's distance, you can also use an
object to set ranges and even rotations for any Array. It could be an
existing 3d Model from your scene or a helper object like an Empty from
Blender.
An Empty is a unique type of object in Blender that will not appear
during rendering. It works only as a helper for modeling, animation, or
any other task that requires a reference object.
You can create an Empty using the SHIFT+A key and choose Empty
with the option Plain Axis for the most straightforward Empty (Figure
4.23).