Kurt Cobain

"It seems that Kurt sometimes used Seymour Duncan Hot Rails pickups, which are humbuckers, but reduced to the size of a single coil pickup, meaning they could be fitted to his Fenders with little or no irreversible damage. In guitars that could fit them, he often used Seymour Duncan JB pickups. "

"Apparently Cobain developed a taste for Fender guitars just prior to recording Nevermind. "I like guitars in the Fender style because they have skinny necks," said Cobain in a late 1991 interview. "I've resorted to Japanese-made Fender Stratocasters because they're the most available left-handed guitars." During this period, he also acquired a left-handed '65 Jaguar that had a DiMarzio Super Distortion humbucker in the bridge position and a DiMarzio PAF in the neck position in place of the guitar's stock single-coil pickups. These modifications were made before Cobain purchased the guitar."

Kurt can be seen throughout this video using the Hot Rails on his Stratocaster.

Kurt Cobain's 1959 Martin D-18E acoustic guitar, famously used during Nirvana's "MTV Unplugged" performance, was equipped with a Bartolini 3AV soundhole pickup. This modification was made because the original 1959 DeArmond pickups did not perform well with the bronze strings Cobain preferred. According to Julien's Auction House, the guitar featured this pickup, as detailed in their listing and confirmed at timestamp 1:56 in their video. Additionally, Cobain's 1961 Epiphone FT-79 Texan acoustic, acquired in mid-1992, was similarly modified. Used live for the first time on September 26, 1992, at the Castaic Lake Amphitheatre, it was later altered by Earnie Bailey to include a 1/4" input jack. By October 1993, this guitar also received a Bartolini 3AV pickup, enhancing its versatility as an electric/acoustic instrument. Notably, Krist Novoselic's Buck Owens American "Red White Blue" acoustic, played by Pat Smear during the In Utero Tour and MTV Unplugged, also featured the Bartolini 3AV pickup.

Kurt Cobain briefly used a Seymour Duncan SJBJ-1 JB Jr. in the bridge position of his Fiesta Red Fender Mustang, as seen during the Roseland Ballroom performance on July 23, 1993, in New York City. This is evidenced by the video "Nirvana - 7/23/93 - [3-Songs] - Roseland Ballroom - (New Music Seminar) - New York, NY" by Alt Copperpot5 on YouTube. He later switched to the full-size JB humbucker.

Livenirvana confirms that this was the humbucker installed in the bridge position of Kurt's vandalism stratocaster.

According to the image taken from Aaron Rash, earnie bailey claims that Kurt's univox hi-flier custom had a Dimarzio super 2 in the bridge position instead of a seymour duncan JB (screenshot taken from https://www.youtube.com/watch?v=wuMyifhHAQQ&t=467s)