Radiosport: Learning - It's All about learning - Part 2

Recently, I wrote a blurb on the fact that, for me, Amateur Radio (in general) and radiosport (in particular) is all about learning.  This last weekend was another oddball, off-contest weekend.
While there were several state QSO parties (IA, NJ, TX & WA), the poorly attended NA RTTY
Sprint and even the Scandinavian Cw contest, the bands seemed noticeably "UN-occupied".

Behind the scenes, a number of occurrences were occurring:

• The SFI dropped from 102 ==> 73 in about 36 hours.
• A revamped RockVille mixer was reintroduced to the portable operating position @W7AYT, paying special attention to Channel 4 (CH-4), with a specific focus on the recently cascaded [NIR-10] ==> [NIR-12] combination fed by the FT-1000mp's less capable sub-receiver.  Reading the e-Ham reviews on the NIR-10 and NIR-12 DSP units,
  it would seem that the like/dislike of any one unit over the other largely depends on one's style of operating versus the degree of  thoroughness with which you read the NIR DSP manuals.
  Both the NIR-10 & NIR-12 manuals describe the unit's functions in 3 (similar, but
  slightly different) ways.  Both manuals seem to have been written by the same "committee", or at least, using the same word processing template.
• Running both units in cascade enables the best features of both units to be utilized,
  altho reading the e-Ham comments has led me to believe the NIR-12 should cascade
  into the NIR-10 - not the other way around (as it is now).  This of course takes us back
  to the Doctor.
  

In 2014 I asked the QST Dr. about the proper way to cascade audio filters and equalizers. 
I've written two Blogs addressing this question: 

• The DR. Validates Cascading Filters

  More Lessons Learned from Listening to the Dr.

In the 1st Blog, I published a copy of my letter which appeared in QST.  While technically the Dr. did not really answer my question, his theory description made for a fascinating look at what goes on "behind" the electrons when signals are directed through
one or more audio processing units.

 

Remember that "filtering" is a function of removing "bits" of the signal.  At the end of the filter chain, most likely the overall amplitude will have been reduced by some "NN" percent.  My solution to
this was an embedded stereo amplifier card inside
the RockVille mixer which was recently written up.  ([CLICK HERE])

Just prior to typing this Blog this evening I rolled out the operating table (it's on wheels), got behind it and amidst the morass of cables, swapped the NIR-12 to cascade into the NIR-10.  

 

Using the DYN Peak facility (in the NIR-12) much of the DSP work is accomplished right there, allowing the NIR-10 to finish the job.  In my Experience, the NIR-10's Notch facility is way superior to the NOTCH Button in the NIR-12, altho ironically the consensus in the e-Ham groups rates the NIR-12 notch superior - maybe the FT-1000mp "has something to do with it".

Therefore miss Addams, in the spirit of learning, it has been empirically demonstrated to MY DeeP satisfaction that the proper order of the 3 filter units for the FT-1000mp sub-Receiver should be: AUTEK QF-1A ==> NIR-12 ==> NIR-10.  While I may find an even DIFFERENT order for all the
filters, for now, I am enjoying this current FB configuration.  Remember: "Underneath" all of this, Stereo-Cw is alive and well, making things even MORE interesting.

What about YOU?
Have YOU played around with nested audio filtering?

What were YOUR results?