Goomz: Good poll question. The quick answer is "yes."
More specifically, I have been known to kick the center channel volume up a notch if I feel the dialog is getting buried in the soundtrack. Apart from that, when listening to two-channel sources, I may adjust the front L/R speakers +/- a decibel or two if I feel the center image (such as a vocal) is leaning too much to the right or left.
Lastly, when I calibrated my subwoofer with the SMS-1, the default volume was 35dB. I have found that a bit too much for most of the stuff I listen to, so I've backed that down 5dB.
It's funny when you do this though; you can wind up dialing in your system to a particular movie or album, forget to set things back, and then before you know it, your calibrations are out of whack!
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Outlaw 970
McCormack DNA-125 (mains), Emotiva LPA-1 (surrounds)
Quad 11L (F&C) Wharfedale (R) LFM1 (Sub) w/ SMS-1
Squeezebox -> Behringer SRC2496 -> Musiland MD10 DAC
Sota Sapphire; Marantz 10B;
Video: Hitachi 42HDS52A; Oppo 971H
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