Most rooms don’t need acoustical treatment.


Why?  Because acoustical treatments presented are in virtually empty rooms. Unrealistic.

my rooms have furniture and clutter.  These rooms don’t really have a need for treatment.  It’s snake oil, voodoo science.  
So why is accoustical panels gonna help?  No one can answer this, most have no clue.
jumia
it all depends on your expectations for good sound. who is to say what you like, or what you will put up with.

lots of my top musical moments have zero to do with the fidelity, and everything to do with who i was with and what i was doing. top down, cruising the 101 in the early morning with my girlfriend on spring break in 71’, playing ’Here Comes The Sun’ on my 8 track is my top musical moment. who cared how it sounded? it was the moment.

OTOH if you do care about musical truth and fidelity then the room matters, and playing room roulette regarding getting lucky naturally does not work for many. symphony halls are not casually assembled for a reason. domestic rooms operate with the laws of physics also (slightly different than large halls for sure).

and at low volumes the room is not very relevant; but if you want to listen at live music volumes, then the room will really rear it's ugly head and make the experience horrible. you blame it on the recording, or the system, but it's mostly the room that cannot handle scale or dynamics.

here are some educational video’s if you actually want to learn about the subject.

https://www.gikacoustics.com/educational-videos/

if you have any doubt on this subject, go to any audio show and walk into 30 rooms and see if they all accidently sound good. if you love them all then find another hobby. this one is not relevant for you.
my friend doesn’t have acoustic treatments in his room

but then again, he is almost deaf

i hear quite well, i need 'em in my room for my system to sound really good
I have the Hifi in our living room and as you can see (from the following pic) room treatment wasn't really needed once the room was properly furnished with our favorite things.

https://media.distractify.com/brand-img/v6qRkZ-ac/2160x1131/sandra-hoarders-clutter-1559584060509.jp...

DeKay
Even for near listening most room need not only passive acoustic treatment but more active controls...I know that by experience and experiments... i know that because i read many times that near listening can spare me acoustic treatment and it is false in my room and physics dont change with room....But many people have not experience this fact because the listening in a moderately big room is not the same experience than in a smaller one....Then near listening in s small room is NOT AT ALL near listening in a way bigger room....

Acoustic is more complex than what we read in audio thread...

A  room is NOT a passive reflecting set of surfaces for the waves of sound to boucing off or be absorbed or being diffused... Like acoustical companies suggest to sell their materials... This is only half the story... A room can be activated and is a potential sets of different heterogeneous pressurized zones.... Helmholtz science...

Acoustic is more powerful than most upgrade...

No speakers at any price could shine in a bad room or even in an ordinary room....