Premier Guitar features affiliate links to help support our content. We may earn a commission on any affiliated purchases.

Builder Profile: Seymour Duncan's Custom Shop Queen - Maricela “MJ” Juarez

Seymour Duncan Custom Shop Manager has wound pickups for a who’s-who of guitar gods—Clapton, Gibbons, Van Halen, Holdsworth, Harrison, and many more. But she’s revered for more than her tonal sensibilities.

Maricela “MJ” Juarez manning her pickup winding station

“The heart and soul of your guitar has to connect with your own heart and soul,” says Seymour Duncan Custom Shop manager Maricela “MJ” Juarez.

Juarez has worked alongside Seymour Duncan for more than 30 years, establishing herself as the legendary pickup builder’s most trusted collaborator. She’s also become a custom pickup builder to the stars, helping the guitar’s most demanding tone junkies connect better with their instruments. Some say she’s wound more pickups heard on gold and platinum records than anyone. Her clientele includes Billy Gibbons, Eric Clapton, George Harrison, Eddie Van Halen, Vince Gill, Slash, James Taylor, Peter Frampton, Warren DeMartini, and Steve Miller—not to mention countless discerning players around the globe.

Juarez began her Duncan tenure as a production-floor pickup winder, but Seymour eventually asked her to manage the growing Custom Shop. It’s expanded so fast that they recently brought in Seymour’s son Derek to help manage. Nowadays they’re only partially joking when they refer to Juarez as the Queen of the Custom Shop. But like so many things in life and music, her path to pickup-winding royalty was anything but what she’d planned.

Tortillas vs. Tone
Just how unlikely is her story? Rewind to early 1983, when Juarez’s then-job moved to North Carolina, while she chose to stay in Santa Barbara, California, with her new husband and their five-month-old baby.

“I was in my apartment making homemade flour tortillas when my neighbor knocked on the door,” she recalls. “She asked for a ride to drop off a job application. I said, ‘Sure,’ but then she saw that I was making tortillas and said, ‘I’m so sorry—I didn’t know you were busy.’ I told her, ‘Don’t worry—I can finish them later, and they’ll be warm for dinner.’”

When they arrived at the neighbor’s hoped-for place of employment—you guessed it, the Seymour Duncan factory—the friend listed Juarez as a reference. Inside, Juarez recognized several employees and chatted with them before heading home to finish her tortillas. But then the phone rang. It was the Duncan shop supervisor with a job offer.

“I started laughing,” Juarez remembers. “I said, ‘Excuse me, you’ve got the wrong person—I was only the driver.’ He said, ‘I know, but I would love for you to come work for us.’ I said, ‘But I didn’t fill out an application! I’m the wrong person!’ but he just kept saying, ‘I know!’”

Day 1: Pickups for Who?
Given the prestige of Seymour Duncan—the man and the company—it’s hard to imagine any pickup winder experiencing a first day on the job like Juarez’s. Not only did she come to the factory not knowing exactly what she’d be crafting, but she also had no idea her very first project would be for one of the world’s most revered musicians: Jimmy Page.

The former Led Zeppelin guitarist was about to embark on a tour and needed new pickups for one of his Les Pauls. “I cannot forget those humbuckers,” Juarez says. “The DC resistances were 8.2 kHz on the neck and 8.8 on the bridge.”

Despite her knack for recalling specs decades after the fact, Juarez is a notorious note taker. She’s chronicled just about everything she’s made at Seymour Duncan, both in general production and in the Custom Shop.

“I started taking notes so I wouldn’t make mistakes,” she says. “I noticed that Seymour also takes notes of almost everything. He said, ‘You take notes? I do it the same way. Look, let me show you!’ That’s when he started showing me notes from when he made pickups for Roy Buchanan, Danny Gatton, Eddie Van Halen, Elliot Easton, Rick Nielsen, and David Gilmour. Seymour liked the idea that I was following in his footsteps on the note taking.”

Juarez says it even became competitive: “I used to say, ‘Okay, Seymour, here’s a customer request,’ and I’d write down my specs without showing him, and he’d write down his. We’d put them together and they’d be the same!”

Between Seymour, Juarez, and others, note taking at the Duncan Custom Shop is pretty extreme. Many large file cabinets hold records of everything they’ve ever made—thousands of full pages mixed in with scraps of paper scrawled with specs.

[rebelmouse-image 25753214 alt="Maricela "MJ" Juarez" original_size="640x451" expand=1]
MJ and Seymour Duncan

Like a Prayer
Under Seymour’s tutelage, Juarez soon learned every aspect of pickup engineering so well that she could tailor units to any customer’s request. Once she knows what kind of guitar you have and the sound you’re seeking, she can prescribe the right magnet type (rough cast, sand cast, or ground smooth), its ideal strength, its wire and bobbin materials, and everything else needed to make the concept a reality.

She throws out a hypothetical: “Suppose I’m talking to someone with a weird request, like, ‘I want a DynaSonic-style pickup to fit into my Gretsch Filter’Tron.’ I have to clear my mind and connect with the caller. Even if we’re talking on the phone, I’m there with them. I might put them on speakerphone while I look for bobbins and calipers, and then measure to see if I need to cut the bobbins or make them taller so I can have enough windings. Finally I say, ‘Yes, I can do it.’”

Though the Duncan Custom Shop has been referred to by that name only in recent years, Juarez contends that custom pickups have always been part of the picture. “I started off with the Antiquities,” she says, referring to Duncan’s highly regarded line of cosmetically accurate vintage pickups. “For Seymour and me, the word ‘vintage’ is like a prayer your grandma taught you. The reason it’s grandma’s ‘prayer’ and not grandma’s ‘recipe’ is because the word ‘vintage’ is holy. You have to go down to the details and keep those things as original as possible.”

She returns to the DynaSonic scenario as an illustration: “If you compare a new DeArmond DynaSonic to an original, you’ll see that it doesn’t have the little soldered line connection that’s supposed to be on the bottom. They don’t take the time to find the parts to do it the original way, but we do. Seymour and I try to make the pickups the way they were made. We tried to find the right little brass pieces for the DynaSonics, but they don’t sell them anymore. So we had to find someone who could tool them up and make them for us.”

You can see why Seymour trusts Juarez—she gets tone freaks. “When you guys have your guitar, you treasure that instrument like it’s part of you,” she says. “It’s part of your heart. It’s part of who you guys are.”

Clone Wars
Considering Seymour Duncan’s roster of famous users, it should come as no surprise that the Custom Shop must sometimes recreate its own past work. For instance, Slash recently requested a recreation of the Alnico Pro II pickups in his legendary Les Paul replica when a new Les Paul he was breaking in didn’t have the sound of the original.

Juarez took the call. “The first thing I asked was, ‘What are the woods in the new guitars?’” she recalls. “Then I knew how to do it.”

Asked how she knew so quickly, she replies, “We know the guitar components and we just have to play with them. The finish might not be the same, the wood might not be as dry or as old, but there are ways to complement the magnets. I was able to deliver him the old tone from his old Alnico Pros using current technology.”

Another recent challenge came when Joe Bonamassa requested replacements for his ’59 Gibson Les Paul. “We took those pickups apart in order to rework them,” she explains. “When we made the replica, the neck position had to be weakened so much that Seymour called it ‘the Weaky.’ We ended up using alnico 3 magnets for the bridge pickup. When we presented those pickups to Joe, he was amazed by how close we came to the tone of the original.”

It probably didn’t hurt that Juarez and the Custom Shop team have an original Leesona winding machine from the Gibson factory at their disposal. However, so much has changed since the early days of the famed PAF pickup that there’s far more to the equation than the right machine. Juarez provides an example: “Without us knowing, manufacturers change the plastic we use for bobbins, or change the material used for spacers.” Even slight changes to the small components sourced from third-party manufacturers can alter a pickup’s sound, so the Duncan crew must constantly listen and take stock.

Thankfully, for many cloning projects the Custom Shop crew can simply consult their file cabinets. Next to the ones filled of notes are others full of duplicates of every pickup made for famous clients. They’re encased in Plexiglas boxes bearing names like Rick Nielsen, Richie Sambora, Eric Clapton, John Fogerty, James Taylor, Allan Holdsworth, Peter Frampton, David Gilmour, and Carlos Santana.

Pulling one out what looks like an old Gretsch pickup, Juarez says it’s one she recreated for George Harrison. She indicates a small screw on the faded gold cover, “It’s rusted right there—this screw is a little more rusted than that one.” Another box holds the prototype recreation of Eddie Van Halen’s original Frankenstein humbucker. “The original pickup has this dust,” Juarez says, pointing out the grooves from the strings bottoming out on the forward bobbin. “We had to deliver all that because it was expected to look exactly like the original. But the original tone has to be there too.”

[rebelmouse-image 25753215 alt="Maricela "MJ" Juarez" original_size="640x414" expand=1]
MJ adjusts a polepiece.

Listening to the Little Guys
Despite Seymour Duncan’s reputation for great vintage-style pickups, the company has an admirable record of staying up to date in its online endeavors. The website offers several ways to compare pickups, including ingenious at-a-glance icons and streaming audio. The site also boasts an active forum where the company occasionally invites participants to help design Custom Shop models. The BroBucker, a super-hot PAF-style pickup with a DC resistance of 10k, is one such design. Who worked with the forum users on this project? You guessed it.

“The BroBucker got its name because it was designed by the bros of the forum,” Juarez explains. Other forum designs include the Crazy 8, which has alnico 8 magnets, and the Fugly Bucker, which is half PAF-style with parallel axis poles, and half blade-style.

If you’ve spent much time in online forums, you’d probably be surprised if there weren’t heated debates on the Duncan forum. One intensely argued subject is whether older JB models sound different from new ones, even though they share the same specs.

Introduced 35 years ago, the JB is Seymour Duncan’s most popular production pickup. But even the JB has been subject to the types of supplier-driven changes previously mentioned. Even though the Custom Shop offers the Antiquity JB with the original specs andoriginal parts, some forum users insist that older JBs sound different, and perhaps better.

Many of the old JBs in question were wound and assembled by Juarez. How can you tell? Each Duncan pickup from that era had a decal with a two-letter abbreviation denoting its model, (“DD” for Duncan Distortion, “CD” for Duncan Custom, and so on.) The initial of the builder’s last name follows the model shorthand. Vintage JBs built by Juarez were labeled “JBJ,” and some believe there’s magic in these particular pickups, which command a high price on the used market.

Here’s Juarez’s take on the controversy: “I don’t know magic, but it could be one of three things: We changed from the long-legged bottom plate to the short-legged one. [Ed. note. This was primarily to accommodate shallow pickup-cavity routes.] We also used to use butyrate bobbins like the ones in old PAFs, but at some point the vendor didn’t have the material anymore. Also, our old magnets used to be rough-cast, but then somebody switched vendors.” Standard JBs are now made with ground magnets, polycarbonate bobbins, and short-legged baseplates.

But Juarez is quick to add that those components might not even factor into the sound of those old JBJs. “It’s mainly how you wind those bobbins,” she says. “The trick might be in winding it kind of tight. That’s why we still have our handwinding machines in the Custom Shop. We have the scatterwinding machine, and we have one of the newer machines. We know that a pickup wound on the newer machine is going to sound different from a pickup with a scatterwound bobbin.”

Even allowing for those differences, Juarez insists there’s too much mythology surrounding the JBJs, and she plans to conduct a shootout between the three different versions. “We’re going to do a sound test,” she says. “I intend to compare one of the old JBs, one made the new MJ way, and a regular production model. It’s on my to-do list.”

[rebelmouse-image 25753216 alt="Maricela "MJ" Juarez" original_size="640x400" expand=1]

All About the Connections
As serious as Juarez is about her work for players of all stripes around the world, she wouldn’t be where she is now if there weren’t more to her than that. One thing that sets her apart is how she goes out of her way for both paying customers and the co-workers she’s come to regard as family—including her famous boss. “Seymour is not like a big brother—he’s more like a little brother,” she laughs. “I know when it’s time for Seymour’s medicine, when he needs to eat, when he needs to go to the doctor. I spend more time here than I do at home. There’s a lot of love and devotion.”

Juarez says she learned her nurturing ways from her mother, who always liked to feed people. As you might imagine, the list of people Juarez has fed includes some of the players she’s wound pickups for, like Eddie Van Halen. “He wasn’t ‘Eddie’ at that time—he was just somebody seeking his tone, but then he became another part of my family,” she says. “He was sitting there eating my tamales, and he says, ‘MJ, where is the salsa?’ I told him, ‘I don’t make tamales to eat with salsa, but I have Tapatio.’”

The regard in which people hold Juarez isn’t confined to her Seymour Duncan family and their clients. Many pickup aficionados compare her to Abigail Ybarra, the revered pickup builder who retired in May of this year after more than 50 years at Fender. While Seymour has long been Juarez’s mentor and “little brother,” Ybarra has been her role model. “She’s a lady who did a lot for the music industry,” says Juarez. “There’s no competition between us because she was there before I was. The only difference is that she mainly did Strats and Teles. She was amazed when she came here and saw how I could do those pickups and many more. Abigail has all my love and respect as a role model, as a human being, and as a lady.”

When it comes to just about every aspect of Juarez, you can measure her success by the quality of her connections—be they between people, or between wires and pole pieces. “I believe in getting into the heart of the individual and finding the tone they are seeking,” she says. “I want to connect with the hearts and souls of musicians through communication, truth, and honesty.”

Maricela “MJ” Juarez