Speakers The single most critical component

What he confuse with "echo" is the walking speed and changes of position while singing of the singers...They move constantly on the stage or in the studio and their head is never fixed but turn right or left singing or speaking... It is easy to hear...In a good room we SEE the singers...

I’m glad you enjoy this recording so much, but your conclusions about what is correct are nothing more than guesses. By manipulating the phase of the signal from various microphones while panning them left - right - left the person mastering the recording can create the illusion of movement when the singer is standing in one spot behind the microphone. I’m not saying this happened, I have no idea how it was recorded, but given it is a studio recording it is unlikely the singers were moving about the room, but perhaps they were. It is also impossible to create a 3 dimensional soundstage (sounds from behind or outside the speakers) without manipulating the signal.

Listen to a recording by Steve Swallow called "Running in the Family" on his album Deconstructed. His bass is waaaaay off to the side completely disengaged from the rest of the music. It is so pronounced I find it difficult to listen to. This effect is created by shifting the phase of the signals in the left and right channels after it is recorded.. Note the word "created." If the same sound arrives at one ear later than the other, (phase shifted) our brain interprets this as the signal coming from the direction of the ear where it first arrives. By manipulating the phase and amplitude of the bass in the 2 channels it can be "pushed" off to the side.

So I agree that if your system/room has issues with phase shifts it will change how the sound is produced, but we have no way to know if what we are hearing is an accurate representation of what happened unless we were there. It seldom is and definitely is not if you hear sounds from behind you. How do you know your system isn't phase shifting some frequencies more than others and exaggerating these effects?

Frankly, all components are important;

duh

Of course a system is a sum of its parts. That’s not the point of the thread.

I settled on Pass Aleph 1.2 mono’s for my amp, then I got Von Schweikert VR-6 speakers.

so you did it backwards. . The point is, various electronics are much more alike than different while speakers vary widely. So find speakers you like then optimize the rest. Matching speakers to amps is a fools game.. sorry to be blunt but can’t come up with a nicer word than fools at the moment

How do you know your system isn’t phase shifting some frequencies more than others and exaggerating these effects?

It is easy to use a test to verify...

https://www.audiocheck.net/audiotests_polaritycheck.php

It is also impossible to create a 3 dimensional soundstage (sounds from behind or outside the speakers) without manipulating the signal.

It is possible when someone use simple acoustic laws..

For example tresholds of timing linked to the first wavefront law

https://www.researchgate.net/publication/223804282_The_relation_between_spatial_impression_and_the_law_of_the_first_wavefront

I use my homemade mechanical equalizer to do it and my Schumann generators grid with the appropriate passive room treatment... But passive material room treatment is ONLY half of my acoustical settings... The more important half is the mechanical 32 tubes and pipes Helmholtz equalizer tuned for the room... I use it in a way to reinforce the first frontwave law for each speaker....And the Schumann generators grid is a complementary help to create this holographic effect... Some company sell costly device to do it with radio frequencies like the shumann generator frequencies... But i never bought any tweaks i prefer to replicate them at no cost...I called this the three controls over the working three embeddings dimension for any audio system: mechanical : ( i use an original method of my own to tune my speakers with springs) electrical: ( i use my own homemade device all along the electrical grid of my house the "golden plates") and for acoustic:( many devices but the most important being a couple of cheap ionizers, S.G. grid, and H. M. equalizer + regular passive teatment balanced between reflective,absorbing and diffusive effects)..
My system value is 500 bucks and all my device controls cost me peanuts...

You forget also that owning near 10,000 files if these artificial effects were only artefacts regularly used i will listen to them on many other files....(Like in some electronic music....I dont like electronic music and listen mainly jazz and especially classical....)

They really walked and turned their heads singing in the studio and the final impression is like a real event...

I feel this impression of 3-d with others classical very good recordings....For example i can " see" the hands of an harpsichordist on his instrument 3-d like if the instrument were in the room...
https://www.youtube.com/watch?v=_R0eCGPhXko

But the sound of this youtube file is horrible....I own ALL the cd she played with his marvellous instrument very well recorded all his Bach recordings...I know this file from the time i was 20 years old to this day70 years old.... This cd was never 3-d holographic 50 years ago even coming from better speakers my Tannoy dual Gold compared to my actual Mission Cyrus 781....but acoustic is more powerful than speakers specs differences between 2 good speakers .... Now I listen all the pedals strokes and slidings,frictions, of the feet and of the mechanical inside the instrument...The instrument is spread our like a 3-d object in front of me out of the speakers not between it, but in front of it and spread it slightly behind the speakers with the keyboard where his hands walk and plays in some "diagonal" spread, the head part of the wood keyboard in front and the end tail behind the speakers...

Same thing with Vladimir Feltsman well tempered Klavier where the piano is in the room completely and fill it wall to wall...

Samething with Chopin piano Nocturnes recording by Ivan Moravec ....

I will stop here....


Regards and best wishes...

Although not ideal, you can mitigate a lot about a bad room by listening in the near field , there is nothing you can do to overcome bad speakers

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Yep, I  never had issues with  room distortion , I listen very near field,  + low/mid gain. 
which makes room issues negligible. 

If you calculate with the speed of sound in a room you will discover that reflected late and early waves mix in the brain with direct waves coming from the speakers under the critical treshold of 80 milliseconds...

Then nearfield listening is not immune at all from the room characteristic.... I verified this myself by many experiments listening always in the 2 positions nearfield and regular in my own room....

The scale from totally bad speakers to very top high good speakers is a LARGE scale....

The acoustical settings of a room can help and put some intermediary relatively good speakers nearer to the top S.Q. at no cost... A room must be mechanically tuned for a specific pair of speakers....I dont use electronic tuning or equalization of speakers from the room response... I prefer to use each speaker  to change the room....

Acoustic is not magic but almost.....

@mahgister  have you any experience with time aligned speakers?  Vandersteen, etc.

Thanks