Sonic Union Promotes Kelly Oostman and Michelle Kerzner, Welcomes Rob DiFondi
Jul. 07, 2021
Sonic Union is excited to announce that it has promoted two Sound Designer/Mix Engineers, Kelly Oostman and Michelle Kerzner, and added respected Sound Designer/Mix Engineer Rob DiFondi to the company. The trio are part of a tight-knit and diverse talent family that specializes in creative sound production for advertising and entertainment.
Steve Rosen, Co-Founder & Sound Designer/Mix Engineer, says:
“Our very reason for being is to help our clients deliver projects at the highest creative and technical level, and the pandemic provided an incredible lesson in making rapid change to meet them in every moment. It was also a year that showed the strength of relationships, both our clients and the team, despite not meeting in a room.”
He continues:
“Kelly and Michelle are both rockstars who have already contributed immensely to Sonic Union in so many ways - with talent, passion, and the willingness to jump in to find the most compelling solutions. We have seen it over time, but it was even more evident this last year-plus. It’s gratifying to have the chance to recognize each of them with well-deserved promotions as we embark on Sonic Union’s next chapter.”
When asked about her early career inspiration, Kelly Oostman says:
“I started making noise until someone told me to knock it off and get a job.”
Luckily, the one she found allowed her to keep up the noise-making, while combining creative mindset with the highly technical experience that comes with mixing and sound design. The partnership between both has taken her from working in audio for the Olympic Broadcasting Service for the Rio Olympics, to time spent learning production and research for the “Tonight Show Starring Jimmy Fallon,” and ultimately to Sonic Union where she has worked for the past four years. Among her audio career highlights, “Anomaly,” a podcast she sound designed and mixed which was featured in Tribeca Film Festival’s first-ever Podcast Selections, sound design for the indie feature film “Give or Take,” recording, sound design and mix for the musical feature film “A Trip to the Moon” and the recently released cast album for a musical called “Brothers Wright,” which dropped on June 30th. She’s also contributed her talent to commercial projects for IBM, Comcast and Smart Water, among others.



Michelle Kerzner came to audio post through her first love of music, and the jolt of recognition that she wanted to be on the other side of the recording booth glass during a class at Loyola University. Retaining what she loves about the creativity of music, Michelle quickly embraced sound design and mixing. Prior to joining Sonic Union as an Assistant Engineer in 2018, Michelle was at Beatstreet in New York and Apex Post in New Orleans. At Sonic Union, she has worked on a variety of projects including a recent Summersault campaign about female empowerment and “A Song of Grace” by Arielle Knight, a film that premiered at Tribeca 2021. In addition to her mixing and sound design work for advertising clients like Dove, Heinz and Catholic Health Services, she recently voiced a Chase campaign and is part of Sonic Union’s casting department. Among the many things she appreciates about Sonic Union is the natural camaraderie she shares with the rest of the team, inspiring an easy spirit of collaboration - which extends to a new band which she hopes will perform live soon.
Rob DiFondi’s vast experience includes successful tenures at Audio Engine and Sound Lounge working with a variety of clients to deliver audio that enhances narratives and engages audiences. Having worked in the industry for nearly 20 years, Rob still gets a charge from seeing his work, for brands such as M&M’s, Calvin Klein, Chobani, and Dunkn’ Donuts, on screen. He appreciates that the global advertising industry has an indelible imprint on pop culture but is simultaneously a relatively small community of creative, passionate people. Among them, his new colleagues at Sonic Union.
DiFondi says:
“I am excited to join Sonic Union for a variety of reasons. We share a common appreciation for the people-driven nature of the industry; They place great emphasis on fostering community, even as they’ve embraced the idea of remote and hybrid collaboration which feels very forward-thinking. They do all of it with a feeling that’s down to earth and true to who they are as a group and as individuals.”
Rosen concludes:
“Rob is a friend and the timing, combined with a perfect series of circumstances, allowed us to come together at this moment. If you know Rob, he is really a wonderful, warm guy who loves what he does - and that shows in his work and the connections he makes with clients.”
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