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Getting phantom image perfectly centered

This is driving me nuts! I can't get the image centered unless I turn the balance control on the preamp to the 1:30 position. I've tested the system from source to loudspeakers from an electrical standpoint, so I know each speaker is getting the exact same electrical signal with a test tone and each speaker outputs the same dB with the same test tone.

So, it HAS to be the speaker room interaction, right?

I've read http://www.linkwitzlab.com/listening_room.htm and I THINK I understand everything.

All of the following measurements are in inches:
The room is 189 long by 144 wide. (15.75 feet by 12 feet)

The speakers are precisely 45.5 inches from the back wall.
They are each 26.5 inches from the side walls with a caveat. The left speaker is 27.5 inches from the window sash, which is 1 inch deeper than the wall. It's 30 inches to the top panes of glass and 28 inches from the lower panes of glass. But measured from the actual wall, both speakers are exactly 26.5 inches from the wall.

The speakers are precisely 90.5 inches apart.

The listening position is pretty close to 45.5 inches from the back of the room. The back of the room is open to the rest of the house and the wall on either side of the opening is symmetric with each partial wall being 36 inches.

Listening to a recording were I know the voice is dead center, the voice is actually just to the left of centered, and I mean "just". Would you recommend moving the left loudspeaker towards the center an inch or two?

What kinds of techniques to you use to "dial it in" when you've got a really revealing system and you are past the "math" and it's all more art than strict science?

I think you should be able to see a picture of my listening room here: http://orion.quicksytes.com/download/file.php?id=3096

My apologies if this isn't the right sub-forum to post this question to.
marktrav
mapman's avatar
mapman
22,199 posts
 
The window to the left and sound reflections from that almost certainly has to be a factor resulting n more reflected sound energy to teh left rather than right.

Do you hear a difference if the shade is up or down?
marktrav OP
24 posts
 
I do hear a bit of difference with the shade down. The image moves ever so slightly to the right, but still left of center.

I ended up moving the speaker TOWARD the window about an inch or so, and into the room about an inch or so, and I now have a centered image and gobs and gobs of depth and layering. Well, I had the depth and layering before, it was just off center. :)

I think eventually I'm going to put some proper wall treatments on the first reflection point of the right speaker and some heavy drapes on the windows and see if I can't put that left speaker back where it was.

In the meantime, I guess I'm ok.

Would it have been better to move both speakers closer to each other to avoid the first reflections? Or was what I did by moving the left speaker further away from center but maintaining distance to the listener (by moving it forward) the best "hack" for now?

I guess whatever works, eh?
ghosthouse's avatar
ghosthouse
4,306 posts
 
I'm in the whatever works camp but do think some room treatments will pay unexpected dividends. By the way - what kind of speakers are those?
mapman's avatar
mapman
22,199 posts
 
Whatever works. Every room is different. Not every setup will have symmetrical acoustics so there is no rule that says your speaker placement must be symmetrical either.

Also all speakers have different dispersion patterns at various frequencies. Its usually a good idea to get a handle on that case by case in order to figure out best placement option faster.

Its always best to avoid early wall reflections for best imaging. The tradeoff is that distance from walls often will lower bass levels. What sounds best always varies case by case. So don't be afraid to experiment and do whatever works. Should not be needed is all is well but having a balance control provides yet another option.
ghosthouse's avatar
ghosthouse
4,306 posts
 
Missed that your system was posted.
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