If I have a moment I can measure both. For the Knowles measures I also noticed that they were often different. After there are several SWFK, I must have at my disposal 3 different reference to SWFK the classic 31736 which is not ammorti, the 32254 and the 32255 which are ammorti. Despite the very linear Knowles curve of the 32255, in reality there are still higher peaks than on the manufacturer curves. All this to tell you that nothing will replace our own curves in real situations.
measuring 28uap or series 33 sonion and the builder curves are very different also