NBC’s karaoke competition “The Singing Bee” lost a sizable portion of its week-earlier premiere audience on Tuesday, though it again built on its “America’s Got Talent” lead-in and was the night’s top program.

Also of note Tuesday was a promising debut for ABC’s hidden-camera skein “Just for Laughs” and a good start for TBS comedy “The Bill Engvall Show,” on the heels of the net’s success with “Tyler Perry’s House of Payne.”

According to same-day Nielsen nationals for Tuesday, “America’s Got Talent” (3.2 rating/10 share in adults 18-49, 10.38 million viewers overall) was down 18% week to week, making it tough for “Singing Bee” to approach its premiere-ratings levels.

In its second outing, the missing-lyrics series averaged a 3.7/10 in 18-49 and 11.03 million viewers overall — down 27% in 18-49 from the previous week, when its bow was the best in key young-adult demos for any new summer series in five years.

After last week’s preem, NBC execs opted to make “Singing Bee” a part of its fall sked, keeping it at 9:30 on Tuesday following 90-minute segs of “The Biggest Loser” (Daily Variety, July 17).

At ABC, “Just for Laughs” opened nicely, with a preview episode at 8 netting a 2.7/10 in 18-49 and 7.91 million viewers overall and a second seg in its regular 8:30 slot improving to a 3.0/10 in the demo and 8.64 million viewers overall. In both half-hours, “Laughs” wasn’t too far behind the 18-49 delivery in the hour of NBC’s winning “America’s Got Talent.”

No Alphabet series has performed better in adults 18-49 since the season finale of “Lost” on the final night of the regular television season, May 23.

The stronger performance in the 8 o’clock hour boosted “Shaq’s Big Challenge” at 9 (2.0/6 in 18-49, 5.42m), as the weight-loss series established highs in its fourth outing.

Also hitting a summer high was CBS’ “Big Brother” at 9 (2.9/8 in 18-49, 7.02m), but the net remains a laggard at 10 with “Pirate Master” (1.5/4, 4.44m).

Fox barely registered at 8 with “On the Lot” (1.0/3 in 18-49, 2.28m).

Over on cable, the series premiere of “The Bill Engvall Show,” which casts the Blue Collar Comedy headliner as a family counselor whose own family is unpredictable, averaged a 1.5/5 in 18-49 and 3.85 million viewers overall in the 9 o’clock half-hour. Preem joins “House of Payne” to give TBS ad-supported cable’s top five original sitcom telecasts of all time, ranking third among total viewers and adults 25-54 (2.12 million) and fourth among adults 18-49 (1.92 million).

Next up for TBS is the return of critically acclaimed laffer “My Boys,” which kicks off its second season on July 30.