Hook’d app lets users step in as lead vocalist

When we first heard about Bob Taub, he was a concert pianist and inventor with some lofty goals. He saw his new technology - an analytical engine that can read sheet music and translate it into sound, or turn a performance into a musical score - as a way to transform how people learn and perform all kinds of music.

For the moment, though, Taub may have to settle for something a bit more down to earth: creating a new app that Teen Vogue suggested may supplant Snapchat as teenagers' "new favorite thing."

Taub's Princeton start-up, MuseAmi, launched its new "video music messaging" app, Hook'd, on July 10. In little more than a month, the iPhone app has already been downloaded "hundreds of thousands of times," he says - about as often as MuseAmi's first app, ImproVox, since its 2011 debut.

With Hook'd, you can record a snippet of a popular song or even the whole thing, replacing the lead vocalist's voice with your own. But not just an everyday version of your voice - a version improved with MuseAmi's powerful tools, which can add echo or reverb, and even correct your not-quite-there pitch.

"It takes someone who's mediocre and makes them sound good," says chief operating officer Ed Hynes. "It takes someone who's good and makes them sound amazing."

ImproVox and Hook'd both use audio-processing elements of MuseAmi's technology, which builds on cutting-edge "convolutional neural networks" developed by company co-founder Yann LeCun. A New York University computer scientist, LeCun was named last year as Facebook's director of artificial intelligence research.

But while ImproVox offers singers a chance to use studio-quality effects on a smartphone or tablet, Hook'd is, well, a bit more in tune with today's teen zeitgeist. It's not just about making music. It's about "dropping a hook" - sharing your rendition of a popular song with friends and the wider world.

MuseAmi, which counts 13 patents and two dozen employees, doesn't provide revenue numbers for its apps, which generate sales by offering extras after free downloads. For instance, Hook'd offers full songs for 99 cents apiece, through partnerships with major music studios.

But if Taub - whose own resume includes degrees from Princeton and the Juilliard School - is riding a tiger, he's also keeping his eye on his first goal: creating software that can mimic how the human brain reads and understands printed music, so it can be translated into sound - and back again.

"You can hear what you see and see what you hear. That was the original idea," Taub says.

If all goes as planned, MuseAmi will realize that concept early next year, with an app tentatively titled MusicPal that can compare a performance to the sheet music it was based on.

Although the user interface is still being developed, Hynes says the new app "will show the notes you were supposed to play beneath the notes you did play." MusicPal could prove to be the ultimate teaching tool, reflecting the experience Taub says initially inspired him: watching a sometimes-frustrated daughter learn violin.

It's not clear what Hook'd users will learn. But it's evident they're already having lots of fun with the app, which offers a "weekly challenge" that this week invited users to sing with their pets. (You can see Hook'd performances at youtube.com/user/hookdapp.)

Still, Taub can't resist the analytical. Showing off one user's "hook" - the term refers to the memorable chorus of a song, such as the Beatles' "I want to hold your hand" - he explained how the young singer, with the screen name Callie_Dollpie, had used the app's tools.

Callie had "deviated from the melodic line at the end" of her snippet from Christina Perri's hit song "Jar of Hearts," Taub says. She had also used echo and reverb, but no pitch correction.

"She's making the song her own," Taub says. And that's a process this musician-turned-inventor clearly understands.

215-854-2776 @jeffgelles