Opteron05: That is quite interesting. You have done just about everything possible to make it work. It is curious that the CD works on a separate system (your boombox) but not in your main system. I have had, on rare occasion, a newly burned CD that would not play at all in my PC system but worked just fine in the main system elsewhere. Perhaps you could try another copy of the test CD. Just a last ditch suggestion!
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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.
How would a Test CD designed specifically for 2-channel audio correctly operate in a 5.1 channel home theater system? With a 3-channel amplifier how would the audio input channels be separated and distributed if there are only 2 to begin with? The Test CD works correctly with a 2 channel amplifier (the boombox) but not with a Home Theater processor/amplifier. Have you tried using a Test CD designed for 5.1 HT?
This is a provocative approach. I have tried to keep things as symmetrical as possible (the room is 10 x 18 with curtained windows along one long wall and seating along the short wall). Ordinarily, I wouldn't expect the bit of difference to cause as much imbalance as I am getting, but this is worthwhile trying as well. I'll get back to you.
In the interest of brevity, I left out some detail that might have misled you. My pre/pro is an NAD T-163. This unit specifically allows the user to select the kind of processing to apply to each input. As such, I have Stereo enabled on the CD input, and Dolby II enabled for the DVD.
So, my expectation of 2 channel performance for the test CD is the same as it is for any other CD - namely, just as if I was using a complete 2 channel setup.
Where the DVD is concerned, the Dolby processing of the audio might make a difference in what I hear, but the source material is not Dolby encoded. As such, with the rear and center channels "dead", if the problem was with the CD player, I would expect there to be a significant difference, with the DVD conforming far closer to my expectations. That it produces an identical location of the dog barking as does the CD player makes me think that the problem lies elsewhere... I hope this is clear.
You are quite correct - you can assume, but it's always better to check. I did switch speakers without finding a change. I next re-did the speaker and amplifier connections. The result of this was encouraging: the left dog now came from somewhat to the right of the left speaker, while the right dog was just where he should have been, centered on the right speaker.
Now, one of the nice things about the on-screen display of the NAD T-163 is that you can easily set the db level for each channel. As an experiment, I increased the level on the left front channel by 3 db and ran the test again. This had only a minimal effect on the dog barks, but the soundstage clearly widened a bit when I tested with the Brandenburg #4.
The next thing I did was to stop eye-balling the centerpoint of the distance between the speakers and actually measure. To my surprise, I found I had been sitting slightly to the right of center. Moving over a few inches made a significant difference.
Given the difficult dimensions of the room, the center seating point is actually at the point of a pronounced Isosceles triangle - acccounting for the exaggerated effect of a slight re-positioning.
Since I can't change the room, I'll do what I can with speaker positioning (toe-in, tilting, etc.) and also see what I can accomplish by experimenting with the processing choices available on the T-163. As I once found with my original components, it may be that filling in with the rear speakers will get me closer to what I'd like to hear from my system.
Many thanks to all from me and also from my wife, who is relieved to know that the barking will be much less frequent.
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.