Do you have the space for room treatments?
If not, it may be time to use the balance knob, if you have one.
If not, it may be time to use the balance knob, if you have one.
Can we assume the voices you are trying to center are recorded that way?
You should be able to locate a voice in the soundstage with certain quality recordings but no guarantee voices are always mixed in so as to occur in the center.
Your room may well be a factor in an unbalanced soundstage left to right but I think that would probably affect more recording elements and not be isolated to voices only.
How far are the speakers from the side walls. What sort of surfaces are on the side walls? How far do you sit from the speakers?
Can you try the speakers along a different wall, even temporarily just to hear the effect?
Don't be afraid to sit a bit off axis if the soundstage sounds more balanced there.
I really don't think there should be this much of a problem unless one speaker is _very_ close to some very reflective surface (something like tile or glass). Our ears are actually pretty good at sorting out reflected sounds from direct sounds (Floyd Toole's book has a lot of info on this).
In the end, if you can't get stable imaging by moving the speakers around, trust your ears and contact your dealer about a possible problem with the speakers.
I think mapman has a valid point. I also find vocals on a number of recordings to be off to the right or left a bit, and I also get perfectly centered vocals, which makes me believe that this is just the nature of the recording. As he mentioned, the rest of the soundstage should shift also if it is a speaker placement/room issue.
Hummm, maybe we should start at the beginning. Are your speakers wired correctly in-phase? Be sure BOTH speakers are wired + to + and - to - or red to red, black to black. If they are out of phase you will never get a consistent center image.
If they are properly in phase, swap the speak wires at the amp end, left speaker to right output and vice versa. If the image stays offset to the same side as before, the problem is likely room acoustics or the speaker. If the image moves toward the other side, the problem is somewhere in the electronics or wiring of the system. Or, it could be a recording that simply places the vocals off center as suggested above.
Can't hurt to verify these simple, but often missed, steps......
Ruebent makes a good point and the tests are well worth doing first and foremost to isolate the problem. If the problem is not with the electronics/wiring you may then want to go and get one of the many test CDs out there that include voice and imaging test tracks. Two that come to mind are Stereophile Test CD #2 and the Chesky Jazz Sampler. Play the test tracks and note the results.
Follow that up with some reading on speaker set-up and room treatments. One thing that I have learned is that speakers do not have to be placed symmetrically in a room to sound right. Take a look at the Sumiko Master Set and Audio Physics speaker set-up methods and you will see examples of this.
You may also try listening to a radio station like sports- talk or news or a talk show, or commercial. These are generally mixed in stereo and sound will most likely be centered. If you have music you are very familiar with as far as sound placement you could try that. I have test cd's that I use when breaking in gear and for demoing and they are tunes I know intimately. Hope these suggestions help.
First, and I apologize for stating the obvious, but your listening position must be centered between the speakers and to start with, the speakers should be identically positioned in relation to the rear wall (and if possible, the side walls). You dont state your room size; if you have a relatively small room I recommend setting your speakers/seating in an equal triangle (tweeters to ears). You may want to bring the speakers apart from one another (increase the six foot space) also, if they are towed in, try facing them straight into the room; if they are not towed in, try towing them in slightly so that the tweeters fire just to the sides of your ears. Youve probably already done all the above, so have you tried making small adjustments to the left speaker only (moving it back in very slight increments)?
Something else to consider is whether or not each of your speaker cables are the identical length. I agree with the above regarding correct phase. Its possible that you are getting some first reflections on the left wall, while the right wall may be diffused or absorbed (i.e.: furniture placement). Again, try adjusting the left speaker (and as stated above, treat the room).
You might post a photo of your setup. IME if one speaker has corner loading (a sidewall and frt wall) and the other side does not (only a frt wall) you will never achieve a consistent center balance.
A controlled directivity monitor versus your full range wide dispersion speaker would be a better match to your surroundings.
Try placing a mirror on the wall at the same hight as the tweeters. Sit in your listening position and have a friend move the mirror along the wall until you can see the tweeter from your seat. Mark the spot and do the other wall. These are the first order reflections. Place something at that spot to absorb the reflections-like a tapistry or some other acoustic treatment. This will go along way to cleaning up reflections and will improve presence, soundstage and frequency tone. For even better results, continue to move the mirror along the wall until you see the other tweeter-this is the second relection. Treat it the same way. Good luck.
Try taking the recording to a stereo store and listen to thier system to see if the voice is centered to begin with.
As said earlier in this thread not all recordings have the voice centered. At home try this, measure the distance for you to the speakers and make that the same distance between the two speakers. Then try moving the speaker that the voice seems to be favoring further away till you get it to be center. Also reverse the output to see if there is a problem with your amp or speaker, is one speaker loader than the other. This will cause the image to be more to the opposite side. Make sure all the drivers in your speaker are working the same.
That can be a big problem. System balance should be checked with a mono signal. You might also find these test CDs of great value: (http://music.barnesandnoble.com/search/product.asp?r=1&EAN=90368003720&ourl=Chesky%2DRecords%2DJazz%2DSampler%2DAudiophile%2DTest%2DCompact%2DDisc%2DVol%2D1) Stereophile Test CD, Vol 1 here: (http://www.enjoythemusic.com/magazine/music/0704/stereophile.htm) Both discs provide tests and tones that make it easy to lock down your central image. The Chesky disc also has a Listening Environment Diagnostic Recording(LEDR), that will show you if your system's soundstage presentation is up to par. Explained here: (http://www.stereophile.com/features/772/)