Do I have a "balance" problem?

My system is in a dedicated room, 13 x 12.5 x 8.5, with one chair centered between the speakers. The speakers are several feet away from the front and side walls. I've treated the room, including absorption panels to deal with first reflections. Here's my issue: to get proper L/R imaging, I have to set the balance control in favor of the right channel somewhere between (depending on the recording) 1:00 and 2:30 on the dial. My system has always been this way and the issue is consistent with both LP and CD playback. I recently auditioned three line stages and each one required the balance control set to the right. By way of "troubleshooting," I've switched tubes, cleaned all contacts, and systematically switched L/R cables on each pair of interconnects one at a time. Nothing changes. There is no degradation of sound in the right channel (at least to my ears) and when the balance is set properly the music sounds great. But I just don't understand why the balance control needs to be set so far to the right. Does anyone else out there have a similar situation? Is there something "wrong" with my system? Thanks in advance for your thoughts.
Have you tried switching speaker connections on the amp so the channels are reversed?
If you have systematically switched the L and R channels starting at the source and ending up at the amp’s end and notice no change in the off centre balance, then you can rule out the equipment. The only thing left to do is switch the speakers from L to R to determine if for some reason one speaker plays louder than the other. If the off centre balance does not shift, it is simply your room, and that is why we have balance controls.
Only thing to add is that there also a possibility that you have a partial hearing loss on the right side. There are on-line tests you can perform to check that out; no substitute for an audiologist but it's a start.
Swampwalker is on to something. Back in highschool I blew out my left ear drum (after getting steamrolled by some huge linebacker). To this day, sometimes my left ear will sound as if its plugged like when I am in an airplane. This makes the sound shift to the right. I routinely have to blow out my ears to get the balanced centered again. I can hear this "plugging" happen right during a song as the sound will shift to the right and the music sounds congested to me. I should have stuck with the chess club like my mom recommended.
Have you actually checked the distance from the center of your listening chair to the tweeter of both speakers? If you have positioned your speakers by measuring from the walls to the speakers there is still a good chance they are not equadistant from your ears. MOST rooms are not perfectly symetrical. Also if you rely on using various things hung on the walls as references for toe in and location, this can also give less than optimum results.

Try tying a string or wire (you don't want anything that will stretch) to the center of your chair and pull it tight to each of your tweeters. This is a good starting point in assuring the speakers are equadistant.
Yeah, probably your hearing if you've done everything suggested. I went into a depression after my hearing was shot in my left ear (someone blew a kazoo into my ear at a bar at point blank range)...I use a digital EQ to "fix" it, but listening will never be the same. Good luck, because it's a real pain in the ass.
Thanks to all for your responses. I have checked everything up to the amp connection, but will now check amp, speaker cables and speakers themselves, including placement. The hearing loss possibility is depressing, but I will enlist my kids to listen and see if they hear things differently. Or maybe I should just not worry about it and enjoy the music?!
I had a similar issue. For me, the problem was with speaker placement. The speakers were equal distant to my chair, within a quarter inch. However, one speaker was slightly further from the back wall and the toe-in was slightly different than the other speaker, perhaps off by just a couple of degrees. I used a laser measure to realign the speakers and all is well now.
Thanks Thaluza. My speakers have not been placed with such precise measurements. I will pick up a laser measure and see what I can do.
Does your system occupy a rack or cabinet in between your speakers and, if so, how far away from the front wall are your speakers? Even if you don't normally have domestic permission to move the speakers out as far as 1/4 the distance from the front wall to the rear wall (a usual recommendation), it might be worthwhile to try them there temporarily to see if what you're dealing with is a sonic reflection off of an object located between the speakers.

If the above doesn't apply to you, then also, sometimes, construction variations within the walls of your room can lead to the acoustic center of your room not lining up with the mathematical center of the room (laterally). You may want to try differing sets of speaker positions left to right with respect to the midway point between the side walls...just to see if it has any impact on the problem or if a new lateral position for your speaker pair can be found that fixes the problem. In the end don't be afraid to try experimenting with longer or shorter distances between the speakers as well, but you can start with keeping it the same as it is now, for simplicity's sake.

In any case, this sort of problem is almost always fixable if you stay with it, so keep experimenting. Regards. John
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If you have access to other systems (friends or stores) you can listen to those to see if you experience the same center image issues. That'd be a quick way to determine if it's your ears or not.

I'm fanatical about getting that center image locked in the right place. A few doesn't take much in some rooms to throw it off. Just a small piece of furniture or a painting on the wall in a certain spot can really pull an image off to one side. Also, it'll vary on some recordings and even a little from track to track at times.

Good luck in getting it sorted out. Let us know the outcome.
****construction variations within the walls of your room can lead to the
acoustic center of your room not lining up with the mathematical center of
the room (laterally)****

Ivan is correct. In my dedicated room, one speaker is placed along a very
thick, brick load-bearing wall; the other speaker is placed along an inside
non-load-bearing wall which (to make matters worse) has a built-in closet.
No amount of room treatment has corrected what is, basically, two different
sounding halfs of the room. The side with the built-in closet is much more
resonant than the other and tends to make center images "pull"
to that side.

Finessing speaker placement has helped a great deal. Placing your
speakers to be equidistant to your listening position may not be the best
approach. Try moving one slightly forward or backward relative to the other
(the speaker's dispersion characteristics will determine which), and play
with toe-in of one or both speakers. It may not be a perfect solution, but you
can certainly help the situation this way. I have even used tubes that I know
to have slightly reduced gain in one of my amps to compensate. I don't
have a balance control on my preamp. Good luck
Once you start playing with room acoustics, things can get pretty complicated in a hurry. The more you play around with panels and such the more you realize how powerful they can be in both helping and hurting sound. One really needs a test CD like the XLO Test CD to sort things out. And there are so many unwanted peaks in the room, including standing waves, reflections and echoes, that Herculean efforts are necessary to fully address them all properly and at the same time not interfere with the naturalness, openness, and tonal integrity of the signal.
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You can also rule out your ears by simply turning around. I think it's room acoustics and speaker placement that are causing your problem. Same issue in my room, left speaker is further from the corner than the right, more rear reflection and sound is louder on that side. When I change the placement of the right speaker, the problem resolves.

I once had an amp that used a timed relay to protect the speakers from any turn on/turn off pulse. After a few years the relay's contacts degraded and affected the sound in a very similar manner. Sometimes the right channel wouldn't even play until the volume passed a threshold level, and at low volumes the left channel was always louder.
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If you suspect the balance difference is your hearing. Get a good set of headphones and adjust the balance control on your preamp. If the sound is centered and the balance control is centered, the problem is in your room or speaker placement.

Speaker placement can also correct a hearing balance problem. Very small changes in speaker placement make a big audible "balance" difference in many speakers. Listen to several different recordings that have strong, left, right, and center, imaging.
Using your balance control is not a major problem. Manufacturers, including many of the big names, put balance controls on their preamps because your situation is fairly common. No harm is done if you have to set your balance control a little right (I'm sure someone will disagree with that).

If you can get a nicely centered image by moving your speakers around, fine, but I wouldn't tear out any walls or anything like that.
I have the same problem, except my balance control has to go the 3 o'clock to lock in a center image. I had several other people listen to my system and they all preferred balance at dead center. I went to get my hearing checked hoping my right ear needed to be cleaned or something (which you should do too if you haven't already), but my ears checked out fine, which really left me scratching my head. (I also don't notice a balance problem when listening to headphones). This issue has remained through a myriad of equipment changes and in three different rooms. Pulling the right speaker forward helps somewhat, but it doesn't solve the problem and I don't like having that much of an asymmetrical speaker setup.

I noticed when I went to shows and some dealers the image was centered with the balance control set to the middle, and what I realized was that in a properly set up room the problem went away. You seem to have addressed first reflecions, but the rooms that worked for me had some sort of diffusion and/or absorption device(s) behind the system -- usually some sort of half-round tower right in the middle or something like that. I haven't tried this in my room yet but will soon. My guess is my ears are shaped slightly differently in some way, which changes their respective sensitivity to in-room reflections. If you take your hand and just change the shape of one ear slightly it's amazing how much sound changes. Anyway, that's my theory. Hope this helps and best of luck. Please let us know if you find a solution.
Also, many recordings have poor balance with the lead vocals and they are "left shifted." So make sure you're using a test CD with a true center image (e.g., the stereophile test CD series) when you're working on the problem.

I'd love to hear from some recording industry expert on why this is the case, as I don't know (maybe it's because the left channel is more important to drivers in vehicles?). I hear it a lot in my system and periodically have to go back to the test CD to reconfirm what I already knew, that the system is set up properly. When I'm listening I am periodically tempted to shift the balance by 1 or 2 db towards the right to "fix" the image center, but if I'm listening very carefully, I've found that this usually smears the image and hurts the sound quality. I've just slowly worked on giving up my obsession with having the vocals come out of the dead center...
Forgot to mention what Cal brought up. I find better and fuller sound with balance set to the middle as well. Big trade off to get a center image. Hoping the room treatment stuff snaps everything into focus.
Cal3713, I seriously thought it was just me this whole time! I too notice that vocals are ever so slightly shifted left of center in my system. Its a minor annoyance but it does take my attention away from enjoying the music.
Just suggesting, but would a volt meter reading at the amps binding post determine the accuracy of the amps output. If it is the same, great, if not, then that could be a problem.
Wow. I didn't expect this post to engender so many responses. I don't have the problem with headphone listening, so I'm going to rule out a hearing deficiency. My room does have two completely different materials in the side walls -- left (facing the speakers) is a wood cabinet with records/CD's and right is a floor to ceiling glass window. I can see how, even though I've treated for first reflections and other reflections on the front and back walls, those two different side walls could create the issue acoustically. I've ordered a laser measuring tool from Amazon and will use that to play with speaker placement/toe-in, but I'm not going to pull out (what little is left of) my hair to get the image dead center without having to adjust the balance. I feel better knowing that I'm not alone, and as a wise poster said here, "that's what balance controls are for." Thanks again for responding.
I don't have balance controls and in the room I was in previously I had a similar issue. I moved one speaker out and inch or two and viola, done.