Is Imaging Worth Chasing?

Imaging is the most difficult aspect of Hi Fi reproduction. Very few systems image at the state of the art. Most audiophiles have never heard a system image at this level and are unaware of this level of performance. 

All Aspects of HiFi reproduction are important. The absolute sound requires each one to be performed at the state of the art and cost has little to do with it. Spending a fortune will not guarantee this level of performance. Some rooms eliminate any chance of achieving the absolute sound.

Ignorance is bliss.  

@thespeakerdude , What most people think is imaging is easy. Your saying this means you have never heard a system that images at the state of the art. I was an audiophile for 20 years before I heard such a system and I have heard 3 systems perform at that level in 65 years. I have not been in the business for a long time and I do suspect performance at this level is more common, but unless you know what you are trying to achieve getting there would be sheer luck. 

The parameters you specify are very important and I will add one more. The frequency response of the two channels has to be identical. It does not have to be flat. Two speakers of the same model are never identical and each one sees a different environment making the discrepancies worse. Even a symmetrical environment can cause issues. Each channel has to be measured and the discrepancies corrected. Doing this with any system on a reliable basis requires digital signal processing. Trying to get there with room treatment and positioning is a trial and error process and you will get there only by luck. The most important add-on any audiophile can get is a calibrated USB microphone with a measurement program. 

@thespeakerdude , Sorry, you are mistaken. Our hearing sense uses volume and phase relationships to locate sounds. Just twist your balance control and see what happens to a singer imaged to the center. If at any frequency one speaker is louder than the other the image is smeared to the louder side. It only takes a decibel to cause trouble. The only way you are ever going to know what your system is doing is to measure it. Then correct it and listen to what happens to image specificity and the background "blackness." 

Getting a system to perform at this level requires an acoustically sound room, proper room treatment depending on the type of speaker, correction of group delays and frequency response variations and finally, the right equipment. Some speakers will never image correctly usually because of crossover design and quality. Point source speakers are always going to produce a diminutive sound stage. I prefer line source speakers which produce a larger, to me more lifelike sound stage. The fewer analog crossovers the better. Lastly, price is no indication. Last weekend we set up a pair of Harbeth P3ESR XD on stands with 12" Martin logan subwoofers controlled with an Anthem STR preamp. Total system price about $12K. You would swear you were listening to a large set of Wilsons and the image while not state of the art was very close, better than 95% of the systems out there.

@thespeakerdude , all I can say is wait till you hear a system that really images. I can only hope you do as they are not very common. 

@secretguy , there is only one line where proper imaging is attainable and it travels perpendicular to the inter speaker axis exactly mid way between the speakers unless you use tricky digital signal processing, then you can put that position anywhere. If you think your system images otherwise then you have not heard a system that really images. Most expert listeners can locate that position by ear within an inch.  

@thespeakerdude , Funny you should mention that. I am in the process of helping my son in law set up his first system. He has limited space so we are working on small studio monitors with subwoofers. We traveled around Denver and listened to a bunch of them. All of them near field. Only two made me believe they could perform at what I think is a reasonable level for a point source system, The Dynaudio Heritage Specials and the Harbeth P3ESR XDs. The 10 or more others ranged from garbage to terrible.  He went with the Harbeths as they are a much better value and the bass deficit will be made up by the subwoofers. What I find interesting is that my son in law, who has extensive exposure to my system went right for these two speakers without me uttering a word. We only talked after the auditions as I wanted him to understand the thinking of an audio sales person. My son in law is a robotics engineer so his understanding of technical issues is immediate. Other than my system and live concerts he is an inexperienced listener. In order to know what to listen for you have to have experienced it. The majority of audiophiles have not. Many of the might have fallen for one of those other speaker which could not image properly if their designers lives depended on it. Imaging is far more complicated than this instrument is on the right and this instrument is on the left. Proper imaging floats instruments and voices in space with nothing but blackness in between, giving each it's proper size and timbre. 

While near field monitors have definitive advantages they are all point source monitors and at the very best capable of a 90% image. Only true full range line sources can produce a 98% image (with the right recording). Even with digital correction and crossovers this is the best point source speakers can do. You can also never get closer than mid hall. With line sources you can get right up front without having to stick your head in the speaker. 

@thespeakerdude , I think both a poor speaker set up well and a good one set up poorly will not image correctly.

There is no such thing as a perfect room. Rooms always create problems although some are better than others. I use 8 foot Sound Labs speakers. Each one disperses exactly 45 degrees. In my room they cover all but a sliver at both side walls, perfect. The cut off is very sharp both horizontal and vertical. I always use heavy acoustic tile behind panel speakers to attenuate the rear waves. In my case that is the only room treatment required. They are crossed to 4 subwoofers at 100 Hz digitally and the whole system is digitally corrected and EQed to my preference. Each channel has exactly the same frequency response.  

Point source speakers require much more room treatment, horns are not as difficult. The best point source systems can image beautifully but they always produce a small image even sitting near field. I have never heard a point source system convince me that I am at a live performance, line arrays can. They also project power better which is why they are used at outdoor and stadium concerts. 

Another advantage of ESLs is that they are "one way" and can be used without a crossover discounting subwoofers. Crossovers are the most serious design issue dynamic speakers have. I think the most reliable way around this problem is digital bi or tri amping. I still prefer passive speakers as I would want more control over amplifier choice and crossover specification. 

@thespeakerdude , Granted the WAF factor is an issue with large ESL. When I first met my wife I had Tympany 3's, the biggest, ugliest speakers ever made. She views the ESLs as large improvement. Most people think they have something to do with the theater and are surprised to learn they are speakers.

I am an old rocker. I dislike wimpy systems. If you know what you are doing and can afford very large Class A amps ESLs will go beyond the pain threshold. The secret is to cross them over to a subwoofer array around 100 Hz. Below 100 Hz the diaphragm has to take large excursions increasing distortion and sucking up headroom. ESLs will make bass but they hate it. ESLs have advantages dynamic speakers can't match. ESL distortion levels are a magnitude lower. They are way more dynamic. Things like snare drum snaps have as much punch as large horns. I am talking about full range line source ESLs (8 feet tall with 8 foot ceilings) not smaller ones. 

Some people prefer the miniature image they get with point source speakers. I have never had a point source system make me feel as if I am at a live performance and I use to be in the business. My system does it all the time usually when my wife is not home. The funny thing is if I play a Blue Ray video concert the volume does not bother her at all. Go figure.

What all of us think is purely a matter of our individual experiences. Systems like mine are a rarity and few people have experienced them. When you say ESL people think of Quads, an extremely limited and fragile speaker. Speakers like the old Acoustats and Sound Labs are a totally different story. Roger West has installed large ESL PA systems in theaters. They are extremely hard to damage. You have to run them through with a spear, not kidding. You will fry everything else before you fry these speakers. I can push 400 watt amps into gross distortion and the speakers could care less.  

The people who have heard them usually come away with the thought that they are one of the best speakers they have ever heard.