Sure. The method mentioned ain't nearly as sophisticated as you may think:
View attachment 223070
One should add those filter options at the very top of the first PEQ section.
*BTW, one should really keep separate presets for plain regular MCH mode and "pseudo-surround" upmixing modes as there are a few crucial bass-management mixing and PEQ settings that may need to be disabled, adjusted or selectively added.
View attachment 223086
But, primarily, the ff. need to be ticked-off:
View attachment 223098
All of this assumes that manual mixing is performed and where the "Room Correction" [sic] module is fully disabled.
Anyway, you might have EQ'd the surrounds to be very close in their objectively measured steady-state FR to the mains, but right during a regular stereo upmixing session, you're likely to find that either side surround or rear surround channel(s) have too much sound coming out of them. Or, maybe it's mainly the front mains'
imaging that appears to suffer badly or seems
muddier, lacks focus, or more
confused in comparison to the original track played in pure stereo 2.0/2.1 mode. The reality is this may be more prominent under certain specific tracks/albums/or types of music.
So... again, as illustirated in the first screenshot, the most simplest thing to do is to apply a wholesale volume level reduction to the offending side channels on an as-needed basis!
A somewhat more complicated and time-consuming secondary method is to apply EQ cuts (mostly rather than boosts) from what has been originally equalized as "flattish" relative to a target curve. You'd have listen carefully by solo-ing and switching back-and-forth between main channels and side channels. Full-range pink noise is used -- although you can also use more band-limited ranges if you really want to focus in on a specific, difficult to balance attribute or trait. So basically the side surrounds relative to the front channels; the fronts relative to the center; the side surrounds relative to the rears, etc. That's without any pseudo-surround upmixing active, BTW.
However, one can also listen as well while pseudo-surround upmixing is active -- using select stereo music and muting individual/paired channels to evaluate what content gets sent to the surrounds and how they actually sound...
Quite frankly, one could just skip the whole listening part and stick with equalizing based on the captured measurements! It really is all up to you how thorough and methodical you want the process to be.
For me, because I'm mixing and matching multiple different monitor types and brands, listening was really quite necessary to confirm things.
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Well, I could post my saved and somewhat more current generic template file for DSP studio in JRiver, but the logic behind the arrangement and options that can be enabled or disabled (even with the written title labels) really needs some explaining -- I'm afraid, that would necessitate a whole different new and rather long tutorial thread.