As a reviewer of dvds I noticed this problem can (sometimes) be a problem inherent in the production of a master. When the sound elements are layered and mixed they can be applied out of balance to what the original producers had in mind. This does happen more than one would expect (along with a host of other mix-up) THX is suppose to over see that this doen NOT occur - hower even they are not infalable and have had their choice screw-ups as well.
When a film master is NOT the problem I have found it is in the amps which most people use. Even in high-end amp/rec. such as Denon there is only so much they can do within the design constrants of the product. I've gone though Pioneers, Denon, Onkyo, and even Proton (remember those?). I ran into this same problem, though at different levels, on each. Having a good center speaker will of course aid in a clear and better vocal presentation - not to mention having it located at the propler location. Settings such as delay, frequency cut-off, balance, fade and volume (even optional special one like "night viewing" or dialog enhancement" can help.
My search for an amp that would fix or aid in lessening this took me to a road not many tavel.
I found that seperate amp and decoders work better. When I swithed to a Sherborn amp that has 7 amps built into a single unit this problem was gone. WIth regular amps even with 120 watts a channle there is still a sharing going on as to which channel is being allowed to use, or rather is "in need" of power on demand. This sharing or designation of power consumption is what causes the center channel to be come "confounded" or over powered by the others - so when it may seem fine during quiter moments when the L,R, SR, SL are not on the center becomes lost when they are on in any combination.
An amp like the Sherborn doesn't have that problem since each channel is seperate with a pure range of power indepentent from the other.
I no longer experience a low dialog during any part of the presentation - excepet when a disc/master has been incorrently balanced.
This is an expensive upgrade- however once you hear it demoed you'll never want to go back. It is quite a different animal in terms of presentation.
I
