You could listen to music, but some measuring capability such as OmniMic (or equiv), would allow you to ideally mate the mains output, with that of the sub.
There exists an ideal time relationship between the two signals, and with the distance setting, you'll be able to either tame a horrible peak, or fill in an empty canyon. Also, you can find the ideal placement and EQ setting for the LF response. This is significant, especially if you don't possess Audyssey (or equiv) goodness. Both work even better.
Superchunks are fine. However, given a finite amount of material, perhaps they would likely do best spread across the most surface area ... ie, more material over more area, trumps fewer deeper well executed traps. A four inch thickness spanning a corner is very effective. The gap is key, as is surface area "seen" by the LF energy. Your rear wall, up high ... all across would be a great start.
If the drivers exciting the room (below transition F) are all upfront, then perhaps the treatment is best served in the rear first. If excessive energy is removed, steps taken to mitigate this are easy. Then add more elsewhere too.
The sidewall panels, IMO, would be best out a ways to take full advantage of the edge effect.
In my experiments with this very situation, it's often best to allow the incident energy encounter the thickness of the side edge,..in addition to the full front of the panel too
. I'd ray trace and determine where the panel would be best placed so the main sidewall hit is attenuated by the panel side, and allow the remaining energy to encounter the front. Grazing angles don't absorb and catch as one would like, so care must be taken. I like thin divider wells too to "catch" energy.
Anyway, bring them out from the corner IMO, so the edge helps too.
Ideally sidewall panels need to be min 4", w/4" gap. If you merely want 4" on the wall, that's ok too if that's the width you wish to forfeit. Maybe 6" on wall, no gap.
Be mindful, as oft stated ... any reflected energy needs to be spectrally as identical as direct sound,....otherwise you're merely filtering the reflection. That said, thick and effective (grazing angles)
, or diffuse, scattered, or redirected. When it comes to early/first reflections, if you absorb, absorb it all.
These two below are significant;
---The issue, the total energy at the LP, is the combo of the direct field, and the reverberant field. The closer any object in the room is that affects the wave launch off the drivers, the more important that object is. That wave-like recreation of the recording, needs to encounter as few physical disturbances as possible early in it's flight. Your sidewall areas are very important. The room, and it's influence, is overwhelmingly your biggest concern. That said, you're doing the right thing, asking the right questions.
---Treating the room, and addressing the reverberant field, is meaningful because if we delay the impact of this energy, there is sufficient time before the reverberation field has built up. This allows us to hear the direct sound energy relatively free from the reflection effects from the room. Attenuating/delaying this room influence adequately, allows the reverberant sound to become a separate event
from the direct sound. This affects imaging, and the intention is to be transported to the recorded event. More realistically, it would be more of a window upon the recorded event...but certainly a step in the right direction.
With the exception of the benefits associated with PVG/Room Gain, the room is quite destructive to the process.
Other than test software, you may try some acoustic bass w/ vocals. Any good driving clear bass lines ... Sheffield Track Record, one of my long time faves (Nathan East is a monster*
) Or you could try the opposite approach, subwoofer crawl method. Place the sub in your LP, and move about listening for smoothness. Listen to sdurani, regarding his (selective mode cancelation) placement strategy.
Remember, the room's standing waves and characteristics
that influence the sound, are determined by the room’s dimensions
-The degree of this excitation entirely depends on the loudspeaker's/sub's position.
-The degree of audibility depends on the listener's position.
These above items are very simple, yet quite critical.The speaker positions determine which modes are excited, and the listening position will determine which modes are heard.
With your bass traps, however you approach them, the room's effects will be lessened. The FR smoother, the decay tighter. When you combined those two attributes, with the careful adjustment of the distance (delay) setting in your AVR/PrePro, the sense of "speed" and clarity will make the whole exercise worthwhile.
Best of luck(*Daft Punk hired him for their current "Get Lucky" track. Solid collaboration. )