Hamburg, I think many people forget that that paper is primarily about providing smooth bass across a fairly wide seating area.
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Actually, the paper is about provding 'repeatable' bass over a wide area. It assumes that you will correct the roller coaster bass curve so that it is smooth at your listening location. The objective of the study is to determine how many/best locations for multiple subs so that the measured response at every/most locations is identical. With that being the case, you can then correct it to be smooth for everyone.
