Droid 4 --> headphone jack --> 3.5 to RCA conversion cable --> receiver --> speakers & sub. I've been experimenting with a new home stereo subwoofer that performs very well when playing CD's. But when playing mp3/320's from google music (google music is supposed to support that transfer when the recording is 320 and google music set at high quality), I'm not getting any sub woofer output. I don't believe that this is a problem with the mp3 recording itself----my sub crossover is dialed up to 160 Hz which is *more* than high enough to overlap with a recording. So I was wondering if the output jack doesn't reach down to 160 hz. That I would find very surprising since it's only about 1 1/2 octaves below "Middle A" (which is 440 hz).