Ali and Hadi Partovi have shared a lot in common over the past 33 years, as one might expect of twin brothers.

They learned to play piano at age nine, switching to guitar a few years later at Harvard University where the roommates and fraternity brothers earned masters in computer science.

But until now, the 33-year-old twins -- leaders in the Internet field who established themselves at Microsoft and LinkExchange -- have never worked together on a startup. That's changing with the announcement that Hadi Partovi -- the former general manager of MSN.com and group program manager of Internet Explorer -- has joined online music startup GarageBand.com, which is led by Ali.

"We have had a lot of independent success in the same industry, and have never actually worked together," said Hadi Partovi, who left Microsoft in November 2005 to evaluate his next move. "It has always been something that we have imagined, if we could put both of our heads together on the same project."

And what is that project? The two Internet executives are hoping to "democratize" the music industry through GarageBand.com, an online service that has existed for six years but is about to get a major makeover.

The code-name for the company's new service is iJam, a name that emerged last week when it was disclosed that the Partovis were working together. The iJam name is unlikely to remain, with Ali Partovi saying that it was simply a "place holder" to draw attention to GarageBand and its new offering. A name for that offering has not yet been chosen, with the full service to be unveiled in the next four to eight weeks, he said.

Up until now, GarageBand.com has focused on helping independent musicians promote themselves.

The new online service will go a step further, helping people more easily find bands based on their digital music collections or recommendations of friends. Part of that will include a way to automatically scan digital music collections from iTunes or Rhapsody in order to make recommendations.

"If you love Led Zeppelin, we help you discover new music by Led Zeppelin that you might not have been listening to or other mainstream artists, as well as emerging artists, that you might not have realized you liked," Ali Partovi said.

Hadi Partovi described the consumer-oriented service as "a social network for your iPod," working behind the scenes to offer suggestions. "We want to be sort of a taste broker for music lovers," he said "If you are a music lover, we would like to know what your tastes are and be the person that you trust for either recommending new music or connecting you with people with similar tastes or to help you share your tastes with new friends." He declined to go into detail about how the service -- currently in development -- will work.

To help carve out territory in the complex music industry, GarageBand.com has lined up an impressive advisory board that includes record producer Sir George Martin, Talking Heads guitarist Jerry Harrison and Yahoo! Music director David Goldberg. It is also nearing completion of a financing round, which Ali Partovi said will bring in about $2 million.

While GarageBand.com is not raising much money, the company has big aspirations. It plans to make money through online advertising and promoting up-and-coming musicians as a record label for the digital age.

"A lot of listeners are dissatisfied with the idea of a music industry that forces new music down your throat so to speak," said Ali Partovi, whose previous company, LinkExchange, was sold to Microsoft for $265 million in 1998. "With the Internet, for the first time, there is a chance for the listener to have a say in what music is going to be discovered and promoted."

The company, with about 10 full time and five part time employees, has offices in San Francisco and Seattle. In addition to Hadi Partovi, the company has named former Microsoft technologist Nat Brown as chief technology officer.

GarageBand.com emerged before GarageBand, the Apple product that allows people to record music on their Macintosh computers. As part of a deal signed in April 2003, Apple and GarageBand.com agreed to jointly use the name.