Bob Greenblatt wants to make one thing perfectly clear: “Smash” is a good business for NBC. The network has big plans to elevate the level of drama and add dimension to the music featured in the show in its second season — in part by recruiting up-and-comers to pen tunes for a new fictional tuner that will factor into the storyline.

Greenblatt, chairman of NBC Entertainment, is irked by the perception in the biz that “Smash” was renewed for a second season only because it has been such a passion project for him. On the contrary, Greenblatt asserts, the show has been a magnet for advertisers and was a quick sellout earlier this month as NBC engaged in upfront ad sales negotiations. And it commanded the highest CPM of any Peacock drama.

“For the first time in a long time, we have advertisers telling us they specifically want to be in that show,” Greenblatt told Variety. “Usually, it’s all about selling big packages (of spots in various shows), but we have advertisers coming to us with new (money) saying they want to be in ‘Smash.’?”

After all the ratings data from the past season was tallied, “Smash’s” perf was competitive with the ratings of other 10 p.m. dramas on ABC and CBS.

Live viewing in the 10 p.m. timeslot is challenged these days because so many people are watching other programs via DVR during that hour. In the live-plus-7 ratings metric, of increasing importance to nets in evaluating a show’s health, “Smash” averaged a 3.3 rating in adults 18-49; that number put the series in a tie with CBS’ “CSI” and “Hawaii 5-0” for No. 1 among 10 p.m. dramas last season (although the CBS shows’ averages include repeat telecasts while “Smash” aired only originals). In total viewers, “Smash’s” average climbed to 9.3 million with the live-plus-7 ratings factored in vs. 6.7 million for the live-plus-same day numbers for its Monday 10 p.m. slot.

Not surprisingly, “Smash” drew an upscale crowd, a pedigree NBC has prized since the net’s 1980s and ’90s heyday. “Smash” was also primetime’s most-watched drama in homes with annual incomes of more than $100,000, as well as among highly educated households.

“Getting all the live-plus-7 numbers just reinforced the degree to which it’s been a success for us,” Greenblatt said. “I would have been surprised if the (DVR) lift wasn’t as big as it was. I knew this show was going to be challenged running at 10 p.m., but we wanted to give it the best possible lead-in from ‘The Voice,’?” which ran 8-10 p.m.

Now that the show has a following, Greenblatt hasn’t ruled out moving “Smash” to a 9 p.m. berth when it returns in midseason. NBC has yet to specify a day or timeslot for the series.

“Smash” was a big priority for Greenblatt in his first year at the helm of NBC: He wanted to make some noise with the innovative tuner-drama format, a project that traveled with him when he made the move from Showtime to the Peacock. He acknowledged that the storytelling hit some rough patches, which spurred the decision to recruit “Gossip Girl” alum Josh Safran, to succeed creator-exec producer Theresa Rebeck as showrunner for season two.

“We weren’t consistent enough in how our character arcs were playing out,” Greenblatt said. “We needed to smooth out those arcs, and Josh is really suited to doing those kinds of stories.”

One of the standouts of “Smash,” of course, was the original music by Marc Shaiman and Scott Wittman for the fictional Marilyn Monroe tuner “Bombshell” that the show revolves around. One big question for producers going forward was how to keep the musical numbers fresh. “The level of sophistication and accomplishment in the musical numbers kept astounding me,” Greenblatt said. “It’s not easy to do week after week once you get into production but we want to keep that up.”

Greenblatt wouldn’t divulge many details, but he confirmed that Shaiman and Wittman are recruiting composers and lyricists to write new tunes for season two. There will be some new songs added to “Bombshell” as it makes its way from its out-of-town tryout to the Rialto. But the season-two plotline will also involve the emergence of a hot new musical that gives “Bombshell” a run for its money in terms of buzz and Tonys attention. And some of “Bombshell’s” key players will defect to the new show.

Greenblatt likened the season-two scenario to the situation on Broadway in 2004, when tuner “Wicked” was the toast of the town but “Avenue Q” came along and scored the Tony for best tuner.

Shaiman and Wittman are specifically looking for tunesmiths with legit experience but haven’t yet had a show on Broadway.

“I love the idea that out of this show we’ll be able to give some new composers a huge break,” Greenblatt said. “We thought it was a great way to open up the sound of our show too.”