Steely Dan music is built from the bottom up. Besides the vocals, the lead guitar, the horns, and so forth, almost every Steely Dan tune has interesting, precise groove with a complex bass line. If you ignore the top end, just the drum and bass are fun to listen to. Don't try that with most groups whose bass and drum lines will bore you to tears.
Example one: in the song Peg, here is the drum groove. Note that the bass, hi-hat, and two hands are all different. Here is the bass line with a melody of its own.
Example two: in the song Josie, follow this inventive bass line also performed by the expert Chuck Rainey. So cool.
If you're interested in one of the distinctive elements of music theory underneath the Steely Dan sound, go here.
By the way, Pharrell Williams gets it, too. See you at 37,000.