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Discussion Starter #1
Greetings!

I'm curious about a stereo effect that I've been able to hear on some speakers but not others, and I would like to know how many folks on the forum have a system that will duplicate the effect.

On the I Ching track "Young Girl's Heart" (Chesky Records), there's an announcement over PA speakers in the intro that's recorded out of phase. On my previous speakers (and even my very cheap Dayton Audio bookshelf speakers), it sounds like the announcement is playing right in my ear, like I'm wearing headphones. There is no mistaking the effect; when I demo'd this track for people on my previous system they would have a very strong reaction to the sensation. On my newer system, the same PA announcement is projected into the room and diffuse sounding, but it doesn't sound like it's right in my ear.

With my previous system, there are similar effects on other tracks that would actually sound like they were behind me, but my newer system will only portray the sounds as off to the sides at best. My new system has better separation of instruments, detail & resolution, a very strong center image, and stereo soundstage the extends beyond the width of the speakers... but the out of phase effects are not as pronounced.

Is this 'headphone effect' a sign of something the speaker is doing right, or is it a sign of something wrong? If it's the correct- or desired- response form the speaker, are there any setup tips to duplicate it?
 

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Speaker placement is the key here. Even toe in of the speakers can change how they sound to the listener. Speakers should never be place to close to a corner and should be out into the room some distance (depending on the design). The tweeter should be at ear level and aimed at the listening position to get the best results.
 

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Discussion Starter #3
Thanks, Tony.

I've been diligent about symetry of toe-in and placement, and I've tried many combinations. I've added acoustic panels at the side-wall first reflection points, behind the speakers, front-wall first reflection, and behind the listening position.

If producing this 'headphone effect' is a sign of a well performing speaker, then I'm beginning to think it may be a fundamental deficiency in the speakers.
 

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Have you tried adjusting your MLP? I noticed a huge improvement by moving my mlp closer to 38% of room length.
 

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Discussion Starter #6
Hi Dwight,

Thank you for the suggestion. Yes, I've tried multiple listening and speaker positions, including the 38% rule.

To Tony's point on alignment, my next step is to invest in a laser speaker alignment tool to make sure they're setup precisely. After that, I think I'll give up on this aspect of their performance.

I bought them for home theater, and I'm completely satisfied with them in that role. I would be completely satisfied with their two channel music performance as well, if I could just get this last measure of imaging/soundstage out of them.
 

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Discussion Starter #7
I get a pretty strong "inside the head" perception with that part of that track. Strength of the effect will depend on head position and L/R balance, too. If the effect is softened with the new speakers, there might be a L/R matching problem.
Thanks for sharing your experience with that track, Audioc. I was beginning to wonder if I was wasting my time chasing a speaker quirk, instead of an expected aspect of their performance.

I'm not sure how precisely the L/R speakers would need to match, but I've set them up using Audyssey MultiEQ, and verified the outcome with Omnimic. The overall levels are matched well, but there is some variation in frequency response between them, but I'm not sure if it's enough to soften the effect. I also wonder if the drivers are not properly time-aligned, or if there are phase or cabinet diffraction issues that are softening the effect. I suppose I could try temporarily wrapping them in 1/4" felt- leaving the drivers exposed, of course- as a diffraction test.
 

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Following tomyvdb's lead, and your own suggestion, precision setup with laser distance meter is your best next step. At $60 to $80 they are not cheap, but after the first success that brings you a "NOW we're talking!" reaction, you will be glad for the expenditure. My trusty Bosch DLR130K, which I bought 6 years ago for about $80, has gotten as much use as any tool I own and is still going strong. I can't tell you the number of times that extra little bit of of setup precision has paid off with BIG soundstage/imaging rewards.

Edit: Watch out for early reflections, too, they can really mess up an effort like yours. Buy some pretty colored foam acoustical treatment squares and a couple of dollar store makeup mirrors, and start looking for possible 1st and 2nd reflection paths that reflect back to your speakers from the LP, and stick a square or two where you suspect there might be trouble. It can make a big difference.
 

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Discussion Starter #9
I'm using the impulse response feature of Omnimic to dial in identical speaker distances. If I'm using the impulse response incorrectly please let me know! Of course, I still need a laser for alignment and your Bosch unit looks as effective as anything.

I have seven 2'x4'x4" acoustic panels currently at first reflection points, but I need something on the ceiling, and there may be other early reflections, so I'll take your advice and get additional treatment.

Do you have a specific time/Db cutoff for what you consider to be problematic early reflections?
 

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Following tomyvdb's lead, and your own suggestion, precision setup with laser distance meter is your best next step. At $60 to $80 they are not cheap, but after the first success that brings you a "NOW we're talking!" reaction, you will be glad for the expenditure. My trusty Bosch DLR130K, which I bought 6 years ago for about $80, has gotten as much use as any tool I own and is still going strong. I can't tell you the number of times that extra little bit of of setup precision has paid off with BIG soundstage/imaging rewards.

Edit: Watch out for early reflections, too, they can really mess up an effort like yours. Buy some pretty colored foam acoustical treatment squares and a couple of dollar store makeup mirrors, and start looking for possible 1st and 2nd reflection paths that reflect back to your speakers from the LP, and stick a square or two where you suspect there might be trouble. It can make a big difference.
This is what i am going to be using... $6.50
 

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Discussion Starter #12
This is what i am going to be using... $6.50
Thanks for the tip. Gonna be a hot weekend here, so I picked up a Bosch GLM 30 and some felt. I plan to stay cool in the A/C and get my speakers dialed in. I figured the laser measurement would help me with overall room setup as well.
 

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Discussion Starter #14
My speaker placement was already within ~1/4 inch left to right in the room, and measured from my forehead to the mid-range driver they were basically perfect (9.997' left vs 10.005' right, thanks Omnimic!). I did need to adjust the front edge of the left speaker by about 1/4 inch for toe-in symmetry. I used couch cushions for additional room treatments.

After that there was no change in the imaging or soundstage.

So I wrapped the speakers in 1" of cotton batting with cutouts for the drivers. Overall clarity improved noticeably, and certain vocals were less "shouty" sounding. Alas, no improvement in imaging/soundstage.

All that's left now is moving some furniture and playing with the toe-in. I'm not optimistic these speakers have it on them...
 

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Discussion Starter #15
Well, I casually placed my old speakers on top of my current speakers, and instantly had an improved experience with soundstage in my test tracks.

I may remove the crossover from my newer speakers and use a minidsp to make a digital crossover and time align the drivers.
 

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I just ordered the SACD version of this to see how it sounds on my setup. :T
 

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Sounds like you have the measurement thing down. Some speakers will do it and some won't, there are a lot of factors. DSP and time alignment sounds promising.
Thanks for all the input, AudiocRaver.

Maybe someone with more time and patience could figure it out with more room treatments and hours of of speaker positioning, but I don't have the heroics for those efforts.

Doing a digital crossover might improve others aspects of their performance at the same time so that's possibly a worthwhile effort.
 

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Discussion Starter #19
I just ordered the SACD version of this to see how it sounds on my setup. :T
Let us know how it sounds.

My former speakers in a fully treated room felt like the opening of the track was playing right in my ear, like someone whispering in my ear. It was a very odd sensation, and there's no mistaking it if it happens. As I mentioned before, when I would demo that track, unsuspecting listeners would have a strong reaction to the sensation.
 
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