Auds looking for a little variety in their drama choices can head over to Wednesdays this fall.

The 10 p.m. hour features the most diverse trio of competing dramas on the week’s sked, as CBS’ forensics crimer “CSI” takes on new ABC soap “Nashville” and NBC’s debuting first-responder drama “Chicago Fire.” Even their locations are well distributed on the map.

The original Vegas-set “CSI,” entering its 13th season and its second in this timeslot, won the hour last fall with an average same-night adults 18-49 rating of 2.8 (bumped up to 3.9 with all DVR playback) and 11.3 million viewers overall (14.2 million with DVR viewing).

While solid, the show didn’t take full advantage of its potent “Criminal Minds” lead-in, and “CSI” could be vulnerable to a tough challenger — especially among adults under 50. Still, “CSI’s” popularity with men should help against femme-focused competish; also, it helps that, unlike a year ago, it won’t oppose any other crime shows.

ABC’s appealing “Nashville,” centered around rival country singers played by Connie Britton and Hayden Panettiere, figures to provide the stiffest competition for “CSI.” One year after “Revenge” became the net’s first Wednesday 10 p.m. success in years (it was promoted to Sundays this fall), ABC has smartly replaced it with a show the “Revenge” crowd might like.

“Nashville” should get a pretty good lead-in from 9:30 p.m. comedy “Suburgatory” (which follows the estimable “Modern Family”) and could match or perhaps slightly surpass last fall’s “Revenge” averages (2.7 in 18-49 and 8.3 million viewers overall; 3.7 and 10.8 million with DVR viewing).

NBC, meanwhile, put up a decent fight a year ago with its top drama, “Law & Order: SVU” (2.1 in 18-49, 7.6 million; 3.0, 9.9 million with DVR), but the crimer moves to 9 for its 14th season this fall to make way for “Chicago Fire.”

The new drama from Dick Wolf feels like a “Third Watch” redux, and doesn’t appear to be the game-changer NBC needs. It could draw some women 18-34, but “Nashville” will be vying for the same aud.

Bottom line: CBS should win in 25-54 and total viewers, but “Nashville” could strike a chord among the 18-49 set.