Not necessarily. I just set mine to the "CD" input, then set it to "pure direct" which bypasses all of the old audyssey adjustments, etc. Then set the volume to 0 dB (reference level.) After that, all of the volume adjustment, audyssey corrections, etc. is handled by the x4500h.
Both your 3310 and 1802 have the multichannel analog inputs (labelled "EXT IN" on the back.) Then you would need to set that AVR to the "multi channel in" setting and then "pure direct." But I don't know if the X3700h has a setup that will output the three front channels while running the rest. I think it only supports outputting either the mains or the second height channels.