Bob Ludwig, who won 13 Grammy Awards during a 50-year career as a mastering engineer and drew some of the biggest names in music to his Portland studio, is retiring this year.

Ludwig said he’ll continue working at his Gateway Mastering Studios on Cumberland Avenue for the next few months to finish projects in progress, but won’t be taking on any new clients. Ludwig has put the final creative touches on recordings by hundreds of high-profile artists, from Jimi Hendrix, the Rolling Stones, Eric Clapton and Bruce Springsteen to Mumford & Sons, Wilco, Beck, Daft Punk and My Morning Jacket.

“I sincerely doubt I would have had the career I’ve had without Bob and Gail (Ludwig’s wife) believing in me,” Wilco frontman Jeff Tweedy said in a statement sent to the Press Herald Wednesday. “Beyond the exquisite mastering of my records and thorough professionalism, I’ve been the beneficiary of their friendship and warm acceptance in a business that has often felt a little unwelcoming. Bob’s the best to ever do it. Go ask your record collection if you don’t believe me.”

As a mastering engineer, Ludwig performs the last steps in the creative process of making a recording. When the recordings are done, in a studio elsewhere, they are sent to Ludwig. In his studio, he adjusts various levels and volumes and tweaks sounds that most of us probably would never hear.

His ear and skills have been in constant demand in the 30-plus years since he started Gateway in 1992, after some 20 years of working for others in New York City. In the days before digital files of music were available, some big stars came to Portland to sit in on mastering sessions with Ludwig. They included Springsteen, Clapton and J. Geils frontman Peter Wolf.

Grammy awards in the lobby of Gateway Mastering, where Bob Ludwig has worked for 30 years. He’s retiring this year. Derek Davis/Staff Photographer

“He’s absolutely one of my favorite people to work with,” said Cheryl Pawelski, a Los Angeles-based producer who worked with Ludwig some 50 times, including on the Wilco recording that earned him a Grammy this year. “What makes him special is that he cares so much and he’s such a fan of music. One year at Wilco’s Solid Sound (festival in western Massachusetts), there were torrential rains. I looked over, and there’s Bob, in a poncho, just digging the sound.”

People involved with the Maine music scene praised Ludwig on Wednesday for being open and welcoming to local musicians and artists, and for inspiring the next generation of Maine music professionals.

“Bob Ludwig is a great example for everyone working in the music business in Maine. He makes you think, ‘If Bob can be the best of the best and do it from here, maybe I can do something amazing too,’ ” said Chris Brown, a vice president of the Maine-based music store chain Bull Moose and one of the creators of Record Store Day, an annual music business event. “He is a lovely, lovely man and a true music lover. He reminds us that you can always be kind to people and that it’s good to show your enthusiasm at work.”

Ludwig, who is in his late 70s, said he and his wife plan to stay in the Portland area but have no specific retirement plans yet. In an email Wednesday, he said he was “slammed” with work that had come to his studio this week and did not have time for an interview about his retirement. But he did answer some questions about what he’ll miss about his work and what basing a business in Maine has meant to him.

THE HARVARD OF MASTERING

“Mastering has been like an intricate crossword puzzle. Every day I have a new album presented to me, often with many challenges to figure out. I’ve been fortunate to meet and work with amazing artists. Some of these people are truly extraordinary in both musical and non-musical ways. They have really contributed to my life,” Ludwig said. “People (in Portland) have treated us so kindly. The arts scene has offered me pretty much as many great concerts and museums as I have time in which to partake. ”

Ludwig had first posted about his retirement on the Gateway Mastering Facebook page in early July. He announced he was not taking on new work as of June 30 and that he was “completing the 30-year journey” at Gateway.

“Music has always been my love. I’ll miss you and the whole music community with whom I’ve worked. I wake up every day enjoying what I do, which has been such a blessing,” Ludwig wrote in the post.

For 25 years, mastering engineer Adam Ayan has worked at Gateway with Ludwig, amassing his own list of high-powered clients and Grammy Awards. With Ludwig’s retirement, Ayan said Wednesday that he has started his own company, Ayan Mastering. He has a temporary studio in Freeport but hopes to find a permanent Maine location. Ayan first came to work at Gateway as Ludwig’s assistant in the late 1990s.

“It’s like going to the Harvard of mastering,” Ayan said of working with Ludwig. “He is such a legend in the recording industry.”

An example of Ludwig’s skill, and how in-demand he has been, came during the 2014 Grammys, when he won four awards:

Record of the Year for “Get Lucky” by Daft Punk with Pharrell Williams and Nile Rodgers, Album of the Year for “Random Access Memories” by Daft Punk, Best Historical Album for “Charlie is My Darling – Ireland 1965” by The Rolling Stones and Best Engineered Album, non-classical, for “Random Access Memories.”

Even when he doesn’t win a Grammy with his name on it, many years there are a dozen or more recordings Ludwig worked on that win Grammy Awards in various categories. In addition to his 13 Grammy Awards from the Recording Academy, Ludwig also has two Latin Grammy Awards.

SUPPORTER OF LOCAL SCENE

Ludwig has been known as a supporter of the local music scene over the years, making time in his busy schedule to master recordings by local bands. Brunswick singer-songwriter Pete Kilpatrick said it was “awe-inspiring” when he and his band got to work with Ludwig on their 2012 release “Heavy Fire.” He said walking into Gateway and seeing records on the wall by Led Zeppelin, Nirvana and others, not to mention all those Grammy Awards, was “crazy.”

“He let us all sit in on the sessions, and we were like kids in a candy store watching him work,” said Kilpatrick. “I don’t know what his usual rate is, but I feel confident he gave us a significant hometown discount. For us to be able to say our record was mastered by Bob Ludwig gave us an extra level of credibility. ”

For many years, bands participating in MAMM Slam, a youth band competition organized by the Maine Academy of Modern Music, would get to tour Gateway Mastering. Meeting Ludwig was a highlight of the tour. (The event has been on pause since the pandemic.)

“I’m working with kids and teaching them how to do this, how to be musicians or enter the workforce in the music industry. So having somebody like Bob just down the street shows them it’s possible, it’s not just something that happens somewhere else,” said Jeff Shaw, MAMM’s founder and executive director. “He’d play the kids some samples in his studio, which was amazing, because nowhere in the world was that music going to sound any better than it does in that spot, in Bob’s room.”

Ludwig grew up in South Salem, New York, near the Connecticut border. His father worked in the family business, a New York hardware manufacturer founded in the 1850s. He played the trumpet through high school and college, and attended the University of Rochester’s Eastman School of Music in Rochester, New York. He got a bachelor’s degree in music education and a master’s degree in performance.

While Ludwig was finishing his master’s degree and also working in the school’s recording department, music producer Phil Ramone came to the school to give a workshop. He ended up offering Ludwig a job at A&R Recording in New York.

He worked for other studios in New York City until the early 1990s. He started his own company, Gateway, with partner Dan Crewe, who was involved in the business for the first few years. He chose Maine partly because his parents had moved here, but he worried at first that being based in Portland might make it harder to get clients.

It did not.

“In 1992 when I started Gateway Mastering Studios, my then partner Dan Crewe had made a great business plan for us and he negotiated all the pitfalls starting any new business entails. I’ll always be grateful to him,” Ludwig said in his email Wednesday. “The 1992 economy meant building the studio of my dreams here in Portland, something that would not ever have been possible in New York.”