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Left / Right Maddening Problem

Hello all,

I have a conventional 5.1 HT / music system: DVD, CD, Pre-Pro, front amp, 3-channel amp for surround and center and self-powered sub.

For a test CD, I use the Stereophile Test CD 002-2, which provides a dog barking to verify left and right channels, a bark that should come from between the two front speakers and an out-of-phase dog bark.

Both the CD and the DVD (with the center and rear channels turned off) exhibit the same anomaly: the left dog emanates from the right speaker, while the left dog comes from the center. Neither is distorted. The center dog bark is perfectly placed and undistorted. The out of phase dog is indistinctly located and somewhat muffled - which is the expected behavior.

Since the CD and DVD are connected to the pre/pro at separate inputs, I think I can rule out the units themselves as being at fault.

I changed the front amp and got the same result. I changed the pre/pro and got the same result. I changed the connecting cables from the CD and the DVD, which also made no difference.

I deliberately reversed the power and ground on one front speaker, which did not help.

Also, I ran the test setup from the pre/pro to make sure that left and right speakers are correctly connected and identified by location.

Lastly, I played the test CD on a boombox to be sure that it does, in fact, produce the dog barking from the left and right side speakers - which it does.

So, now I am unashamedly stumped and am appealing to you all for help. (My wife would also appreciate a resolution to this issue since my testing is making her nuts.)

Any and all suggestions will be welcomed.

Thanks.

Jon
opteron05

Showing 2 responses by tobias

tobias
1,534 posts
 
Another last ditch suggestion: look into speaker placement and room effects. Is your room symmetrical, for example? My rear wall has a 12-inch step on the left side and when my speakers are not precisely toed in the image shifts to the left.

My reference on this subject is Jim Smith's Get Better Sound.

http://www.getbettersound.com/
tobias
1,534 posts
 
Well done Jon! Thanks for the follow-up.

The next thing I did was to stop eye-balling the centerpoint of the distance between the speakers and actually measure.

That worked for me too. I set up according to Jim Smith's suggestions ( it's a good book--really ) and things were fine. A week afterwards the image had gone screwy, and it took a measuring tape to tell me that I was not actually sitting where I thought I was.

It may seem like barking madness to others, but when it's just right there's no denying the difference.
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