A stupid question for which there's no sensible answer.

Anybody that has lived through an acoustical room transformation personally  KNOW that most upgrade before that is often  a lost of money...

Alas! all the sellers wanted to sells.... And most people had no idea that the acoustic is the main point in audio, not the particular design of an amplifier or of a dac  and not even of speakers...Any relatively good gear will sound marvellous in a good acoustical settings and bad in a non controlled  small room...

Before i worked it i have also no idea, and it is way more easy to think about buying  the illusion and elusive  perfect new gear to be satisfied than thinking about acoustic...

It is complex yes, but ANYBODY can listen and move or install something and improve one step at a time....

An equalizer is a good tool yes, but even without we can but  on a long period of listening taking the time to figure it all...

Keep hope if an ignorant and uncrafty man like myself can, anyone can....

ill listen to a $500 audio system and be polite and say  Sounds pretty Good 
  Then run like hell to my house and get my ears fixed . Let's get that right 

@mahgister, we are on the same page.

@669326  Dear OP, it does not work like that. You are going to continue to get 'advice' and most of it will contradict itself unfortunately. In my experience only a very small percentage of those keen on reproducing music bother to treat the room, even fewer bother to try and understand the 'how and why'

For example: I have seen it stated that you should just cover all walls in egg-crates. This represents narrow-band absorption, and narrow-band thinking!  So what will happen?  The frequency that has the same wavelength as the depth of egg-crate will be absorbed and because there is so much of it that music info will be missing. GONE. The rest of the spectrum will carry on reverberating around your room totally unaffected.

The above situation happens because some well intentioned ignoramus puts that out on the forum. It also exposes him as someone recommending something he has never tried but is merely regurgitating what he read elsewhere, because anyone who has egg-crated the whole place would upon hearing the result, immediately rip it all out.

My best advice is to educate yourself. Get on the net and read articles by those who know what they are talking about. For the cost of a cheap interconnect cable you can buy a mic. This cable will make no real difference (the room won't let you hear the tiny change) The mic. however will allow you to significantly improve your sound. Your choice.

@OP, when I suggest searching on the net I do not mean a forum like this. There are groups specifically about acoustics. Here are 2 links to get you started.

https://www.gearslutz.com/board/studio-building-acoustics/

https://www.audiocircle.com/index.php?board=73.0

Famous acousticians sometimes pop in to advise.

 Here is some fun stuff.

https://www.youtube.com/watch?v=OLNFrxgMJ6E

https://www.youtube.com/watch?v=JPYt10zrclQ

In a recent post on this subject I mentioned a mate with a small almost square room with no carpet, only one flimsy drape and very little else. Think tilled bathroom acoustics. Truly dreadful. He has a lot of money tied up and is constantly spending more trying different components. He has a collection of very expensive cartridges that he keeps trying in the hope of improving the sound. All the fine detail the carts. are capable of is simply lost in the mess of sound waves banging around his room untamed. Last time i visited he had Spread Spectrum Technologies amplification and had replaced his Appogees with Maggies.

In other words the average poster on these forums?  :-)