Originally Posted by batpig
The setting for listening to unprocessed 2-channel stereo is the "DIRECT" mode. There should be a button that says "DIRECT" or "DIRECT/STEREO" on the remote.
However, in order to make sure "DIRECT" is actually unprocessed, you have to check a couple of settings in the AUDIO SETUP menu (pg 33-34 of the manual).
The 1909/789 allows you to have different speaker setup/crossover/EQ settings for 2-channel listening (DIRECT or STEREO mode), because what sounds good for 2-channel music isn't always the same as for full-on surround sound.
If you check out pg 33 of the manual, under AUDIO SETUP, there is a sub-menu called "2ch DIRECT/STEREO".
Go into this menu, select "Custom" (if you leave it at "Basic" it will just use the settings you set up for general surround use), and then set up your front towers as LARGE and set Subwoofer to NO, and then set your speaker distance manually (use a tape measure or estimate or whatever).
Next, go into the sub-menu called "EQ PRESET" (also in the AUDIO SETUP, pg 34 in the manual) and under "Direct Mode", turn MultEQ to OFF.
Now, when you are listening to a CD and hit DIRECT, you will be listening to unprocessed, 2-channel music, with Audyssey totally disabled, played through your front towers with no crossover and no other speakers involved.
If you want to start involving the sub (for 2.1 stereo) or Audyssey's EQ curves, you can play with all the options in those two sub-menus to get 2-channel stereo listening as you want it.
(Also, on a side note, if Audyssey is screwing up your crossover settings feel free to change them manually to something more reasonable like 80Hz. Check out the official Audyssey thread and do some reading, changing the crossover manually won't mess anything up)
Hope that helps!