But what's most surprising is how authentic and faithful Tremonti's renditions of these classic songs are.
A longtime Sinatra fan, Tremonti says he went down a Rat Pack rabbit hole a number of years ago, reading every Sinatra book and listening to every record he could get his hands on.
"It's been the project of my dreams," Tremonti tells Q104.3 New York's Out of the Box with Jonathan Clarke. "I absolutely loved working on this, I think it was the most exciting thing I think I've ever done in my life."
The album, Tremonti Sings Sinatra, arrives May 27. Not only is it Tremonti's first effort as a bonafide crooner, it's also the first of what he says will be many collaborations with the newly-minted Take a Chance for Charity.
All proceeds from the album will benefit the National Down Syndrome Society (NDSS). Tremonti began working with NDSS about a year ago after his daughter was diagnosed with Down Syndrome.
"There was a reason for this obsession [with Sinatra]," Tremonti says. "Frank Sinatra raised over a billion dollars for charity. That's not something that a lot of people talk about. I'm going to sing a Frank Sinatra record and do it to raise funds and awareness for charity."
At first the album was a fun, departure from Tremonti's heavy metal world. But then he learned of a connection to Sinatra's world; his manager used to take guitar lessons from one of Frank's touring guitarist.
"So it went from my just doing a covers record to me doing it with Frank Sinatra's actual band," he added.
Check out the full conversation via the player above!
Listen to Tremonti sing "I've Got You Under My Skin" below!