WILL THE REAL MAXIMUM SPL PLEASE STAND UP?
Measured Maximum SPL vs Calculated Maximum SPL and how not to be fooled

Introduction
When purchasing powered loudspeakers, most customers compare three key specifications: price, power and maximum SPL. Unfortunately, this can be like comparing apples and oranges. For the Maximum SPL number in particular, each manufacturer often has its own way of reporting the specification. There are various methods a manufacturer can employ and each tends to choose the one that makes a particular product look the best. Unfortunately for the customer, this makes comparing two products on paper very difficult.
In this document, Mackie will do the following to shed some light on this issue.

Will the real maximum SLP please stand up?