• by Wayne Friedman , July 3, 2013

NBC’s big summer show “America’s Got Talent” fell again to a season low -- but NBC won the top spot overall on Tuesday night before the big July 4th weekend got underway.

“Talent” was at a Nielsen preliminary 2.3 rating/ 7 share among 18-49 -- the show falling from a 2.6 rating a week ago.

NBC lead all contenders among key 18-49 viewers on Tuesday night -- at a 1.8/6; Fox, 1.5/5; Univision, a 1.4/5; CBS, a 1.2/4; ABC, 0.9/3; and CW, 0.2/1.

NBC was also tops among younger 18-34 viewers with a 1.4/5; and among total viewers with 7.38 million. Fox and Univision were in second place among younger 18-34 viewers, each with a 1.3/5. CBS was second among total viewers with 5.985 million.

Another summer contender, CBS’ “Big Brother,” got to a 1.8/5, a series low, down from a 2.2 from its last outing a week ago. It was second on the night to “Talent” among 18-49ers. Both shows aired opposite one another at 9 p.m.

Earlier that night, Fox’s summer competitor “So You Think You Can Dance?’" got to a 1.5/5, off its 1.7 rating the previous week. The only other original programming, “Betty White’s Off Their Rockers," at 8:30 p.m. was at a 0.8/3. A week ago it was at a 1.0 rating.