It may be simply the difference in acoustics in 3 different rooms (?)
That's probably it.
My computer has a Logitech 5.1 system, and the default is "simulated surround" (front is duplicated in rear),
If your Mastering in stereo, then listen to it in stereo while doing so. Use only FL + FR. for this.
Thanks - that's another avenue to pursue....I also read an article on "loudness", which may account for some of the
shock of certain tunes (boisterous country rock) SOUNDING LOUD as opposed to gentle classical pieces sounding
much quieter, even thought the db output is about the same....But i'll definitely do the mastering in stereo and see if
that helps it to sound a little different in the first place. I know the subwoofer tends to bring out a lot of road noise
(scenes shot in a moving car) that i don't hear on other players....