Sorry for my poor reading comprehension. When I looked back at the formula it says right there use between 100hz and 12 khz for one part and 100 hz and 16 khz for another part.
Also noticed looking in Toole's book about Olive's work on this, something I had forgotten. That subjectively judged response below 250 hz typically is several decibels higher than the anechoic curves indicate. Usually 10 db higher at 50 hz and 6 db higher at 35 hz. Something which would seem to explain exactly the now much discussed lack of low end as measured on the Magnepan LRS vs what people hear. People hear it as lightweight and in need of a sub, but not nearly so lightweight as the Klippel measurements show. And this is perfectly expected from the prior work. It just looks so glaring because the LRS has that peak around 400hz and rolls from that point on down.
The PIR is supposed to help this issue. 2 issues though:
1) It is tilted; thus I normalize it to its own slope (I used to do it to the target slope, not anymore). I then do a weighted average with the on-axis (weights per the formula). This is my Tonal Balance tab in my files.
2) It is going to still under-estimate the bass, as it doesn’t account for boundary gain. This effects all speakers though, and of course the gain is different per room and placement. But yes, when it is very lean in the bass, the data makes it look even moreso.
EDIT: The LRS is very directive in the bass, and it has the cancellations at +/-90°, thus the bass it puts out into the room has to be less than other speakers, even if the on-axis was flat, but since that is also down, no favors are being given. But, since the panel sits close to the floor, there will also be some reinforcement there (not much more compared to a 3-way pair of towers, but more than a 2-way bookshelf on stands).