Most rooms don’t need acoustical treatment.

Treatments are more important for Maggie owners IMHO.  Planars radiate in both directions.  It is important to have a diffuser behind the speakers.  It makes a world of difference.  I cannot cannot comment on box speakers as I have not owned one in the last 20 years.

Mr lemonhaze,
thanks for your thoughtfulness. 
I need to learn more about bass freqs.  So much too learn.

I purchased 2 bass traps for the front wall behind my speakers. The difference was revelatory. Today the FedEx truck brought 5 more panels, and I spent the morning experimenting. Again, revelatory!

 "These rooms don’t really have a need for treatment.  It’s snake oil, voodoo science."

You are kidding us right?.. Trolling... The SCIENCE of Acoustics... voodoo.........

Skeater says, "Aunt Millie, she ain't right in the head."  

You are listening to two rooms.  The room where the sound was recorded, and your listening room.  You have a choice.  Listen to one, or both.