Speaker Imaging - Do you hear a line, or do you hear an arc??


Hi Everyone,

I am not trolling, I genuinely am interested in your experiences.


When listening to a system you feel images well, how do you perceive the sound stage? Do you perceive it as a rectangular space on which the speakers sit, or does it sound like an arc, going further back towards the middle?


Please give examples with music and speakers if you have the time.


Thanks,
Erik
erik_squires
The basics are pretty simple, in my experience and based on audio science.  I've been fortunate to be able to experiment with a wonderful array of spaces:

*  Sidewalls -  the closer they are to the speakers the more your image is anchored on the speakers while forming a "U" between the speakers (speaker output is reinforced with short delay reflections).  For best imaging, you should for all intents and purposes have no side walls within many, many feet of the speakers.

*  Wall behind speakers:  The further away, the more "depth" you will perceive when it is recorded on the recording.  The closer behind, the less depth.  (Of course, you have also to pay attention to room nodes for accurate bass reproduction.)

*  Prevention of center "cross-contamination".  Experiment with center reflections from the wall behind the speaker.  To experiment, put a six foot high stack of empty boxes with one corner ("v") centered and facing out behind the speakers.  This breaks up reflected diffusion from between the speakers.  In a real room, this can be approximated many ways, including a "v" shaped two panel screen if needed.

This is the simplified basic.  It can be approximated different ways with room treatments.  If you are lucky, you can even arrange a living room this way.
Harrylavo made some excellent recommendations, if I may paraphrase:

- We want to minimize the early sidewall reflections, ideally with distance.

- We want to minimize the early reflections off the wall behind the speakers, again ideally with distance.

- We want to re-direct the early reflections off the wall behind the speakers so that they don’t bounce directly towards the listening area.

If I understand correctly, the idea is to manage early reflections in a way that reduces what might be called "small room signature". By that term, I mean the aural impression of being in a small acoustic space, rather than in the acoustic space (or "soundstage") on the recording. (Notice Harry is not advocating absorbing these potentially detrimental early reflections - I’ll come back to why his is such a good idea in a minute.)

There is in effect a competition between the acoustic signature of your listening room and the soundstage on the recording. The acoustic signature of the room is primarily conveyed by the first reflections, and the acoustic signature of the (typically much larger) recording venue is primarily conveyed by later-arriving reflections. Notice this key aspect of harrylavo’s recommendations: He is NOT using absorption, so he is PRESERVING the beneficial late-arrival reflections! (In particular, he is preserving the SPECTRAL BALANCE of these late-arrival reflections).

How is the ear/brain system able to pick out these soundstage-signature reflections on the recording from the later-arrival reflections that come from all around the room?   By matching the spectral balance of these reflections with the spectral balance of the first-arrival sounds.  Thus it is important that these reflections be spectrally correct, or nearly so. To the extent that absorption alters the spectral balance of reflections by selectively absorbing shorter wavelengths, it is weakening the soundstage signature we’d like to enjoy.

I’m not saying that absorption is always a bad idea, and often it makes a worthwhile net improvement, but if we can find a benign acoustic solution to detrimental early reflections - like harrylavo’s recommendations - ime that facilitates hearing the soundstage on the recording. Not to mention the richer timbre we get from a well-energized reverberant field.

So imo the more we can do to minimize small room signature without degrading beneficial late-arrival reflections along the way, the closer we can hope to approach that elusive "you are there" kind of presentation.

Duke
the closer they are to the speakers the more your image is anchored on the
speakers while forming a "U" between the speakers (speaker output is reinforced with short delay reflections).



That's probably at least partly my issue.  << sigh >>
It depends in varying degrees on the recording, how deep and how wide the stage is and how well placed are all the instruments and vocals, but always, my Maggie 1.7s disappear from the performance. On good recordings, regardless of where I set or stand, the vocals and instruments stay focused in their space and on a stage behind and beyond the plane of the speakers. I did spend a great deal of time and effort in room treatment and speaker and equipment set up - important with Maggies....Jim
don_c55  That is one of the three reasons I stopped using stats after more than 20+ years.  My wife couldn't enjoy (or me) the sound to the sides.  I purchased big dynamic speakers instead.  The Von Schweikert Ultra 9 and 11 speakers are so special as they permit a huge seating area with tremendous depth and width beyond the speaker positions.  I hope to replace my Legacy Focus with the VR55K in the future and enjoy superior width and depth as well.
I have a very expensive customized listening room so acoustics are not an issue (it’s always been the speaker which limited my imaging/soundstage equipmentwise). I note that the 50’s/60’s small jazz recordings were commonly left, right track recordings with a soloist in the center (especially Rudy Van Gelder's). Funny though, my hi end tube preamp replicates what is on the recording with sharp left and right sound at the mike sound while a switch to my lesser EAR 864 preamp spreads the sound out in a line from speaker to speaker but lacks 90% of the depth of the hi end pre-amp (custom made). The more accurate sound is the hi end unit but the lesser unit is very pleasant sounding albeit inaccurate. That same period large jazz and orchestral recordings sound best with the most filled in sound between speakers and good height (placing instruments on various levels on a recording stage if not on a flat stage). Vocalists vary from 4’ to 6’ high, probably many of my recordings are inaccurate in height where the majority are heard at ear level. Left and right recorded strings and soloists are often at the plane of the speaker. Hence, better/newer speakers would help my sound (mine are 25+ years old and not SOTA but really fantastic for $2500).