[Sonic 748i]

I would guess it's the speaker's ability to respond to that impulse signal on the dime?

 

[khaos974]

I'd say how well your room is treated, but if you are only talking about the speakers, I'd day the  variance between the pair you are using.

 

[Jack C]

In my experience, which echos khaos974, the most important issues include left/right channel matching, and room treatment. Other biggies I would say include tweeter resolution and dispersion pattern. Crossover and enclosure design all factor into these.  I once heard a pair of Paradigm speakers that were in the middle of a busy showroom floor. It imaged exceptionally well sitting there and I listened to it for a long time before the sales people chased me out.
 
When it is done right, the results are startlingly good. When done poorly, you wonder why they even bothered building the things - seems like a terrible waste of natural resources.
 
Jack

 

[Krav]

Given the speakers are matched, the room treatment is adequate, and the listener is inside the stereo sweet spot, it is a flatness of the speaker's frequency response curve and accuracy of phase matching between a given speaker's transducers.
 
The science behind that is well explained somewhere around page 200 of this excellent book: http://www.amazon.com/gp/product/0240515129 .
 
Anecdotally, I played with digitally controlled self-tuning sound systems where I could set a "perfect" frequency response and phase coherence, and at this precise point the localization of instruments would become laser-accurate.
 
Imperfections in the frequency response result in sound sources moving around when they change their main frequency. Very annoying with violins and vocals. For more frequency-discrete sound sources, like grand piano, the image becomes larger than it should be.
 
Phase incoherences result in sound sources being imaged as fuzzy clouds instead of solid objects.

 

[khaos974]

Room reflections and the type of speaker (dipole, monopole...)
 
Very interesting read by Siegfried Linkwitz: Room optimized stereophonic sound reproduction, if you ever heard of the Linkwitz-Riley filter, it's the same guy.
By the way you may visit the entire website, it's full of interesting information, notably about the Orion DIY loudspeakers, which have a very good reputation.
It's a active 3 away open baffle dipole speaker design, unfortunately, the plans are not free, even if they remain modestly priced.

 

[Krav]

I was initially excited about the Orions, bit became much less so after I listened to them for about couple hours (you can connect with your local Orions' owners through the Web site).
 
Very capable system for sure, yet I found its frequency response too uneven for my taste. The uneven frequency response in combination with massive reflections does indeed create "phantasmagoric" effect where instruments appear to move around in some kind of magic fog. A curious, even mesmerizing effect, yet I like more accurate reproduction where I can hear less of phantom sound and more of original one. Your mileage may vary of course.
 
Quote:

Room reflections and the type of speaker (dipole, monopole...)
 
Very interesting read by Siegfried Linkwitz: Room optimized stereophonic sound reproduction, if you ever heard of the Linkwitz-Riley filter, it's the same guy.
By the way you may visit the entire website, it's full of interesting information, notably about the Orion DIY loudspeakers, which have a very good reputation.
It's a active 3 away open baffle dipole speaker design, unfortunately, the plans are not free, even if they remain modestly priced.

 

[khaos974]

Thanks for the critical opinion, yours is the first negative review I've heard about the Orion+s, I was quite taken by the idea of getting them built or building them myself after reading how they were designed but when it came to reviews, a bit of leeryness is good especially with DIY products where ownership bias is even stronger.
 
I wonder what the best brands are when it comes to stereo imaging, ME Geithain? K+H? PMC? Adam?
Are there speakers that go further than an active crossover and move the crossover in a DSP?

 

[Krav]

I probably should have been more explicit - I don't have a negative opinion about Orions. In their own way, they are quite attractive. I guess the closest to feeling like smoking pot without actually smoking it It's just that smoking pot or enjoying music enhanced in a surreal way is not my thing.
 
The Orion owner who gave me the demo was in fact a big time audiophile and a very intelligent and knowledgeable guy overall. Definitely with a budget to own anything he wanted. He also had an enormous DIY subwoofer paired with Orions that could be classified as a battlefield weapon He even had treaty with neighbors regarding the times he could use it.
 
That owner was the closest one with Orions in my area. He generously gave me two hours of audition and questions and answers time. I brought four or five CDs and SACDs I knew intimately, and he played his favorite tracks. It was a very pleasurable experience. Yet I was somewhat disillusioned about Orions by the end of it as I'm very sensitive to frequency curve peaks and valleys, and to my ears it sounded like Orion had plenty of them - inherent in the dipole design I believe.
 
As to the monitors, they have their strengths and weaknesse too. At the time I bought Adams A7s, they were known to have a hint of sibilance at high volumes, yet that was of no concern to me, as I exceedingly rarely listen at very high volumes. Another issue was their bottom end rolling off rather rapidly at 45 Hz down, but I already had a Velodyne servo sub that worked perfectly fine up to 120 Hz with very low distortion, so that was not an issue either. And of course they are close-field monitors, which suited well my rather compact physical setup yet could be very counterproductive if the room is, say, over 15 feet in length and width.
 
I also considered Mackie and Genelec monitors at the time. All the rest of those one could find and A/B at Guitar Center or a similar pro-music store sounded not as neutral to me. As to the more exotic ones, including some with digital signaling throughout, they were too much for my budget as I wanted to buy 7 channels for watching Blu-ray as well, and the one mega-bucks exotic I did audition didn't sound all that much different from A7s to me anyway - I think my hearing is not as sharp as one of some professional musicians and sound engineers who go for the K+H and such. Thus Adams A7 for me. I like them a lot, yet they are not necessarily the best for everyone.
 
Quote:

Thanks for the critical opinion, yours is the first negative review I've heard about the Orion+s, I was quite taken by the idea of getting them built or building them myself after reading how they were designed but when it came to reviews, a bit of leeryness is good especially with DIY products where ownership bias is even stronger.
 
I wonder what the best brands are when it comes to stereo imaging, ME Geithain? K+H? PMC? Adam?
Are there speakers that go further than an active crossover and move the crossover in a DSP?

 

[khaos974]

Quote:

Originally Posted by Krav /img/forum/go_quote.gif
 
He even had treaty with neighbors regarding the times he could use it.

Most important factor in stereo imaging , can' listen if your neighbours complain all the time.

 

[Uncle Erik]

Interesting, Krav. I haven't seen this criticism of the Orions before. Still, I've got most of the parts to build a pair (yet no time at the present) and intend to finish the project. But I'll keep your remarks in mind when I evaluate them. I wonder if the owner's room might have had something to do with what you heard.

For me, the phase alignment and crossover make the biggest difference in imaging. No crossover is perfect, so you have some inherent problems there. I got great results from 350Hz up with the ribbons I built and also really prefer singledrivers for their cohesiveness. The Quad ESL-63s I'm running sort of have a crossover, but they're the most coherent speakers I've listened to. Hopefully, I'll end up loving the Orions, too.

 

[Krav]

Orion's owner was very cognizant of the room treatment and speakers placement. We discussed that in length. But with dipoles, there is just too much going on. Figuratively speaking, they will search for and latch on whatever smallest standing wave opportunity they can find.
 
The idea behind Orions is that they produce so many reflections and standing waves that the phantom sounds cancel each other out in the domain of the brain's neural sound processing circuitry and the listener is left with clean original sound. I guess it happens with some people. Obviously the owner liked Orions a lot. But it did't work for me.
 
I also could see the annoying rainbow effect on DLP projection TVs when 99%+ of population couldn't, so I guess it is just a peculiar genetic trait. My brain doesn't average signals well. The opposite side of coin is that I tend to notice more temporal details, both in visual and audio domains, than most people.
 
By the way, Orion's sweet spot was very small. To feel the magic, you'd need to find it. In that particular case, it was marked on the floor and there was a special un-echoic chair for the listener helping to fixate the head position. Only one person at a time could fully enjoy the experience.
 
Once more, I don't think that what I said was a criticism. Orions do produce "out of this world" sound field. I perceived it as vaguely resembling some of highly reverberant artificial sound fields that Yamaha has in its recent 7.x amps. But richer.
 
It just wasn't my bag of tea. I like more precise, clean, some would say "cold and analytical" sound. Just a personal preference that I hope you don't perceive as me imposing on anyone.
 
Quote:

Interesting, Krav. I haven't seen this criticism of the Orions before. Still, I've got most of the parts to build a pair (yet no time at the present) and intend to finish the project. But I'll keep your remarks in mind when I evaluate them. I wonder if the owner's room might have had something to do with what you heard.

For me, the phase alignment and crossover make the biggest difference in imaging. No crossover is perfect, so you have some inherent problems there. I got great results from 350Hz up with the ribbons I built and also really prefer singledrivers for their cohesiveness. The Quad ESL-63s I'm running sort of have a crossover, but they're the most coherent speakers I've listened to. Hopefully, I'll end up loving the Orions, too.