Never...
First i am not a practicing acoustician doing it each week as a job...
Second i do it ONLY one time, tuning mechanically a room for the speakers and not just equalizing the speakers for the room , takes me one year 7 day on 7 ... I did it for fun after retirement and because i could not invest money in audio anyway... Then TUNING a room is like a piano tuner tuning a piano tone chord after tone chord; but in a room i did it with a grid of resonators ( 100 resonators) ...And a balance between diffusion/absorption and reflection as in classical material treatment... I also use foldable screen to focus the waves in the right way to my listening position... The end results was no headphones could compare to my room acoustic not even my actual AKG K340 ...
How can i do it for someone else ?😁
Each room dimensions, geometry,topology, various material acoustic content, influenced the resonators grid distributions and tuning... all this must be tamed and understood by the ears for the tuning process... There is no easy recipe i can apply in one week even a month as people selling and marketing acoustics panels or electronic equalization ... i must seat, listen, tune a bit , listen retune a bit , etc and this is done for my EARS not for other ears ( each inner ears filters are different ) .... 😊
A dedicated acoustically tuned room will cost, designed professionnally, around 100,000 bucks...
No one can do that in few days...Not even a pro acoustician... Few months yes... And for me 1 year...I did not do it by habit for decade as some acousticians do...
It is not putting panels onwalls , along with a ready made computed recipe...Balancing a room reflections is not enough , tuning ask for changing the zone pressures distribution...
My room was resembling to an array of organ pipes, all around me, and beside the speakers, like a serpent with a head (right speakers) and a tail (left speakers) and i use pipes of different size, some big bottles too which are anyway natural Helmholtz resonators... We cannot do that in a living room...😁
Having experienced that, it is the reason i smile at people bragging about costly upgrades in a living room... Sound experience come with acoustic first and last not with cables and gear...
But we dont have the time all of us , knowledge and the free room to do it... It is one of the main reasons why people always unsatisfied upgrade endlessly...
They seriously think that cables can do miracles or dac at 15,000 bucks, instead of a 1000 bucks one, can do it but acoustic is anyway secondary for them , after buying panels at best all acoustic can do is done... Such is the audio marketing world...
Which gear designer anyway could spell the acoustic beans TRUTH and saying so, putting his design in the secondary seat as a mere servant of the most important thing to do ? And which audio magazine can write: forget about costly upgrade, do your room ... And even if they say so, with what ? Acoustic panels ? Acoustic panels are very good and effective when well done but it is not enough to create a dedicated tuned room with a soundfield immersive enough to beat any headphone and with spatial holography ....
The best scientific way to do it now exist if someone own an already well done acoustic , not a tuned room , only a well done acoustic is enough if he buy the BACCH filters of Dr. Choueiri... The greatest acoustic revolution in audio... Read about it... Forget any other upgrades...
Acoustic is the sleeping princess, the kissing prince is your brain/ears, and the gear pieces are the 7 working dwarves...
@mahgister It would be interesting to see what you could do fine-tuning this listening (or any listening) room. Ever consider hiring out your services?