For a 1967 album that managed to yield a number one hit single and an additional Top Ten smash, Album 1700 was pretty out of sync with contemporary trends.

This is not exactly a rock record, but the trio was unquestionably making more use of backup musicians and arrangements that owed a bit to pop/rock.

(Paul Butterfield, Paul Winter, Canadian rock band the Paupers, and top New York folk-rock session musicians Paul Griffin, Russ Savakus, and Harvey Brooks all play on the record.) They never did sound too comfortable with that form, but at least they didn't sound as uncomfortable as they had in the past.

The material was an uneven mixture of passably pleasant original tunes covering light comedy and social/philosophical commentary, including an honest to God folk-rock cover of Eric Andersen's "Rolling Home," albeit with the pure folk harmonies of their early days unchanged; a Bob Dylan cover ("Bob Dylan's Dream") that could have easily fit onto a PPM album early in their career; and, perhaps to make sure there was one song for the toddler when it was played in the family living room, the positively embarrassing "I'm in Love With a Big Blue Frog." "I Dig Rock and Roll Music," though it made the Top Ten, was not a wholehearted embrace of the new rock sounds, coming off as a rather savage and strange parody of the Mamas & the Papas.

The album's ace in the hole was the melodic and slightly maudlin "Leaving on a Jet Plane," an early John Denver composition that would became a number one smash in late 1969, two years after the LP's release.