Seth MacFarlane on His Surprising Connection to Frank Sinatra — and How He Acquired His Lost Archive (Exclusive)

Seth MacFarlane thought he heard every Sinatra song. Then he recorded them himself.

The creator of Family Guy speaks exclusively to PEOPLE about his new album Lush Life: The Lost Sinatra Arrangements, which contains unrecorded songs from decades ago — along with his surprising connection to Frank Sinatra.

MacFarlane’s association with Frank’s son, Frank Sinatra Jr., goes back to his animated comedy series, Family Guy. Frank Jr. appeared on the show several times, and MacFarlane, 51, “got to know him somewhat well.”

“He always kind of had a bit of insight regarding classic orchestras and pieces of information that I didn’t know each time he would come in,” he says, adding that he’s a “buff when it comes to orchestras from that era.”

“In addition to that, he was the steward at the time of all of the arrangements that his father had accumulated over the course of his career.”

Following Frank Jr.’s death in 2016, his sister Tina Sinatra was the steward of the arrangements, with whom he grew close.

“She was looking for a home for all of these charts and asked me if I would be interested in acquiring them. The goal being not to have them sit in a museum somewhere collecting dust, but to have them played,” he continued.

After he took over the charts from Tina, 77, MacFarlane realized that many songs in the archives were never sung by Ol’ Blue Eyes, dating back to the late ’50s and early ’60s.

“We hired an orchestra, went over to Fox [Studio Lot] and played as many of these things as we had time for, and discovered that there was really a whole album here, songs that for one reason or another he had decided not to perform when they were written.”

MacFarlane says there were “so many songs that had just been sitting there in boxes for seven decades, just waiting to be found.”

“I had always assumed that I had heard every Sinatra recording ever made and heard every song that was ever, or every arrangement that had ever been written for him, and that wasn’t the case.”

The Grammy-nominated singer estimates there are about three albums’ worth of songs in the archives.

The most difficult part of the process was recreating the same warmth that Sinatra brought to his arrangements and recordings. Oftentimes, orchestral jazz in the modern era has a homogenized, sort of antiseptic kind of feel to it,” says MacFarlane.

“Over the years, there were things that we learned, specific things that we discovered through research as far as why it was that those recordings sound the way they do. Part of it was that we record to reel-to-reel tape as opposed to digital, and that gives you a warmer sound.”

With an orchestra of 70 musicians from the U.S. and U.K., MacFarlane was able to turn the arrangements into something “a little more enduring with a great arrangement and a great approach to the recording.”

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MacFarlane was a longtime Sinatra fan, but his admiration grew deeper throughout college after he bought a “Best of Sinatra” CD and listened to a recording of “Three Coins in the Fountain.”

“There’s something really special going on with this guy’s arrangements,” he recalls realizing. “This sounds like I’m listening to a film score that is being sung to. That’s, as I found out later, was sort of the norm for Frank.”

“There are recordings, particularly in his ballads, where you’ll hear a minute-long intro from the orchestra before the vocal even comes in. That was something that I really responded to,” adds MacFarlane, comparing them to a karaoke track that lacks variance.

“The Sinatra charts were very different. There was so much going on in the orchestra, there was so much happening and so much detail that even without the vocal, it was just kind of a work of art on its own. That was how I kind of found my way into Sinatra, sort of a reverse-engineered type of thing.”

As for his favorite Sinatra record? Frank Sinatra Sings for Only the Lonely from 1958. “Everyone involved, the arrangers, the recordists, Sinatra himself — it’s just everyone at the peak of their talent and at the peak of their career,” he says.

Up next for MacFarlane is a limited engagement at the Voltaire at the Venetian in Las Vegas.

“We’ll be doing some songs from this new album and a bunch of other stuff as well with about a 35-piece orchestra,” he says of the three shows, taking place July 3-5. “It really will be an old-school Vegas experience in the real sense. It’s a serious bunch of musicians and I’m looking forward to it.”

Lush Life: The Lost Sinatra Arrangements is available to stream.