PROAC D48R Bass Booming

I will try this, definitely.

Is it really the case where the speakers sound great with most recordings, but is too boomy for some?  Could it be that it is still a bit boomy with most recordings, but not so troublesome?  I ask because any sort of permanent fix to reduce the booming will also affect the sound with recordings that you are not troubled by.  It might be the case that an equalizer will be the best approach for you--you can then do recording-specific adjustments.

It may also be the case that a set of subwoofers will work.  You can adjust the crossover frequency and thereby cut the levels of bass coming from the ProAcs and then adjust the bass from the subwoofers to your liking.

In any case, your approach of doing more experiments with placement will always be the best first step.  But, do not assume that farther from the back or side walls will always reduce the booming bass.  There could be points that are actually near the walls that will do the trick; it is a matter of finding points that reduce reinforcing nodes and cancelling nodes.  I also generally like bass traps in room corners.  

Dear all,
                I am updating the latest development.  I sold the BAT VK 3000 SE and replaced it with a pre-owned Karan KAI 180 Integrated Amp.  I tried plugging the Downward Port with Foam.  Trust me, 80% of the Bass boom is gone and now I am listening bass-heavy tracks without much difficulty.
                 My sincere thanks to all.

Great news and happy to hear it worked out for you

these speakers very much. But the only problem is Bass-boom and because of that, some tracks are unlistenable.


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I think ProAc uses Scanpseak woofers, 
Yes?
WEll this **boominess* in upper bass, is part of that drivers character.
Which is why I went with Seas Magnesium to avoid the upper bass resonances.
I think Wilson also uses Scanspeak.
Scanspeaks offer incredible low bass. Tight punch in drums. 
Every driver has its tradeoffs.
Paper composite  vs magnesium.