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Please help, obsessive audiophile question

Ok, I did something really bad to myself, I got the XLO test CD. What I discovered was a channel imbalance, that, I think, is due to my room. Here is what I did:

First, using a laser, I perfectly centered my speakers in the room, and dialed in an equal amount of toe in on both sides. Also, again using the laser, I checked for dead center on the listening position and dead centered the components between the speakers.

Next, with the balance control centered, I ran the 315 khz test tone on repeat, and measured the voltage at the amp terminals. The voltage was nearly perfectly even. I repeated this at several volume levels, and usually was within a few percent. What ever variation occured between the channels was randomly split between left and right.

Next, the balance test on repeat. With the lights and my eyes closed, I used the remote to adjust the balance on the preamp to center the voice. I started out in the centered, extreme left and extreme right positions, and did my best to make sure I was unaware of how much adjustment I was dialing in. I repeated this multiple times, and got perfectly consistent results. I end up with the balance control turned about 4 "taps" to the right, which translates to a 10% voltage in favor of the right channel at 315 khz. I do not have a sine wave generator or ocilliscope, so I can not verify this over multiple frequencies, but my "aural" measurements have proved to be very consistant.

I adjusted a few moveable items in the room, but, due to some furniture that can not be moved, I think I am getting more reinforcement from the room on the left side.

So, what to do? Will this balance adjustment adversly affect my tube amps? Will one side go through tubes quicker? Should I try to move one speaker back? If I do move the one speaker back, will I adversly effect the time alignment between the two speakers? Or should I stop stressing and just leave the balance control off center.

I know it sounds compulsive and weird, but it sort of bugs me to see the balance control not dead center. Again, this IS an obsessive audiophile question;)

Thanks in advance for all your thoughts.

Ron
rlips
fefer77
37 posts
 
you might be getting more gain from the left channel monoblock - switching amps would prove it. it might be the room although in your picture the room looks quite symetrical - what's going on behind your listening position? i probably wouldn't bother about it though - like Khaki8 says that's why you have a balance control.
electric_monk
38 posts
 
Swap the speaker cables left to right and keep the speakers the same position. I know it aint perfect but it should answer the question of whether or not it is downstream from the speakers or "at" the speakers. If this doesn't change anything then get to lugging.
deano
77 posts
 
Even though each speaker may be placed EXACTLY the same distance from the listening position, the room's shape and funishings may influence apparent channel balance. Move the speaker whose volume is down, closer to the listening chair. An inch and a half did it for me. Good luck....
g_m_c
443 posts
 
Van Goth would have simply cut off the imbalanced ear.
rlips OP
105 posts
 
Thanks for the responses so far, it helps to know there are others like me out there!

Fefer77: I think the gain is ok, as I measured the outputs of the amps to be fairly equal. I already switched the amps around, no change.

Electric_monk (great moniker, btw): I can't do that, I have really short cables, the advantage of monoblocks;) I will probably lug, but I will have to enlist some help, so I can't do it right away.

Deano: I might end up doing that, but I was concerned about messing anything else, as I have the rest of it dailin in nicely. I think I will try it though, as I can always go back.

G_m_c: I agree, but the question is, where exactly should I begin the cut? Do I cut off the entire thing, or try to balance it by just cutting a little at a time? Should I use a stainless steel knife or would that give the system a "metalic" sound? Should I cryo the ear? Sorry, I digress, but at least I am smiling now.
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