I'm not sure if this is interesting or useful to anyone, but I did a little more testing with the X1X tonight, focusing on power draw and noise. As with last night, I measured the output with the phone directly on top of the X1X, but separated by a 1/2 rubber pad to minimize vibrations. My tv is a Panasonic VT65 VT65 1080P plasma, so the X1X is down sampling for my purposes. Power draw was measured using a Kill A Watt P3.
Power draw at outlet, standby mode: 13 watts
Ambient room noise: 22-25db
As above, with X1X on at dash: 22-25db
As above, with WD 4GB My Passport Ultra plugged in: 24-27db
As above, with TV turned: on 24-27db
As above, power draw at outlet: 47 watts
Game observations:
COD WW2 averaged 29db with 156 watts measured at outlet (Stronghold mission)
Return of the Tomb Raider was 32db in performance mode (162 watts), and 33db average in enhanced mode (183 watts). I did not try 4k mode downsampled.
Wolfenstein II averaged 33db with 199 watts measured at outlet
FM7 averaged 32dB and 151 watts measured at outlet (4 lap race at Homestead, overcast turning to rain)
Titanfall 2 averaged 33dB and 173watts measured at outlet (post patch today)
Since Wolfenstein posted the highest decibel reading at 33, I measured it at my normal seating position 9' away, which yielded 23db; so in my case, the sound dropped off considerably.
Despite the fluctuations on the power draw between the different games, the sound at the console remained fairly consistent.