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It is sortof incorrect to think of SR and A type as a boost of frequencys like the RIAA or Academy curve as it is not
It is a selective boost of frequencys at different amounts depending on the level below a threshold
One of the problems with most of the cloned NR cards is they have a linear downward expansion slope while in fact the colby system has a set of knees to them

I am not at all the league of you two technical guys but I have a question and a comment. First, our new theater came with Frazier speakers which we suspect are 30 years old. They performed acceptably with stereo sound. We just completed the hook up of our 3 year old Dolby CP500 processor and amps brought from our previous theater. It ran with the Fraziers for about 2 weeks. The sound was not nearly as wonderful as it is now that we have installed the brand new JBL speakers behind the screen. (The surrounds are still Fraziers until we get the new JBLs hung). The subwoofer still has to be wired in also. This theater did not come with any additional wiring so we still have our challenges. However, my point is that there is a seriously audible difference that even I can tell between the old Fraziers and the new JBLs without any change of surrounds or subwoofing. Beware of old speakers!

Now for the question. Our DTS screen probably was installed in the rush to get Star Wars Episode 1 but it was probably bought used (it is an old 2 drawer unit). However, the theater also has JBL speakers in it. We don't know how long they have been there. They could have been as new as the DTS conversion. The DTS apparently was never installed properly and caused lots of passes to be issued when the sound cut out completely in the auditorium for extended periods and the show was lost. It now works properly and all systems have been tuned and balanced. However, the JBL subwoofer failed in the last month and was sent out to be re-coned. They say that it was dry rot. It has been returned and re-installed but I wonder what caused it to fail in such a short time and whether it will fail us again and need to be replaced. Any thoughts?

Frazier was never the greatest of speakers they used a lot of old RCA designs
The last ones they made when the moved were rather revolutionary in there time alignment but lacked power handling (the cat serries)

All paper cones eventually rot and some of the JBL subs use a foam surround that eventually fatigues and fails
Also it is a good idea to dust them off everyso often as if there is a lot of polution in the area it may leav particulate that accelerated the process

Both Frazier and Peavey have put together some rather odd looking speaker packages that I would find hard to be enthused about... No speaker likes sunlight exposure or a damp enviornment... Heavy paper woofer cones (especially when they are rubberized or plasticized) can last a very long time... Foam surrounds have a very limited life expectancy, especially if driven hard, and fabric reinforced or butyl reinforced accordian edge woofers are by far the best choice for long life... That JBL sub may have been used or stored in a damp enviornment before it came to you, and if you are driving it hard, it's a race between dry rot and mechanical fatigue to see which will do it in... Next time, I would look into a replacement with a reinforced accordian edge surround...