Planar-magnetic and true ribbon dipoles, hand-built in Minnesota since 1969, from the .7 to the four-panel 30.7.

James M. Winey was born April 18, 1934, in western Iowa, grew up on a farm and took an engineering degree at Iowa State. After a stint at John Deere he joined 3M in St. Paul in the fall of 1961, where he led the design of packaging machinery. He was also an electrostatic enthusiast: he owned Janszen Z-600s bought from Bill Johnson's Minneapolis audio store, traded them for KLH Nines, and at Johnson's shop heard a wall of prototype electrostatic panels that he called the closest thing to a live performance he had ever heard. Around 1966, on a 3M project laminating tape to flexible magnetic material, he looked up at the perforated acoustic ceiling tiles and saw how a magnet sheet could be made acoustically transparent. That night he built a prototype from refrigerator-gasket-grade magnetic material, adhesive tape and a copper-wire voice coil, drove it with a Dynaco amplifier, and heard no bass but a purity of sound. He worked on the driver part-time until 1968, and in June 1969 left 3M with $50,000 raised from about thirty friends and relatives to found Magnepan in an industrial building in White Bear Lake, Minnesota, shared with an auto-repair shop.

The patent, US 3,674,946 for an electromagnetic transducer, was filed December 23, 1970 and granted July 4, 1972, assigned to Magnepan Incorporated. Winey's single full-range panel was too directive, so the first product took a three-panel folding-screen form, bass drivers in two panels and a narrow high-frequency line source in the third, at the suggestion of William Z. Johnson, who had just founded Audio Research. The Tympani I went on sale in 1971 at $995 a pair, with Audio Research as Magnepan's first distributor, an arrangement that covered only the three-panel Tympani series and lasted about five years. The MG II of 1973 began Magnepan's own dealer network, and the word Magneplanar was registered as a trademark. In 1978 Winey and his marketing manager, Wendell Diller, saw a pair of Tympanis fitted with a Sequerra ribbon tweeter at Lyric Hi-Fi in New York; Winey sketched his own on the flight home, direct-driven with no transformer, a line source and a dipole, and the Tympani IV of that year was the first Magnepan with the true ribbon tweeter and the first flagship the company marketed itself.

The late 1970s and 1980s were the volume years. In some months Magnepan shipped more than a thousand pairs, and its one product that was not a loudspeaker, the Unitrac unipivot tonearm, sold about ten thousand units in four or five years. The MG III of 1983 brought the ribbon tweeter to a single-panel speaker, and Stereophile's Martin Colloms, reviewing the three-way MGIIIa at $1,995 a pair in January 1987, wrote that in no way could it be dismissed as old technology. Through the late 1980s and 1990s foil-trace quasi-ribbon drivers replaced wire conductors on successive models, the MG1.5/QR before the MG1.6/QR, while the MG2.5/R and MG3.5/R carried the true ribbon. The three-panel Tympani had grown too large for most buyers, and in 1995 the single-panel MG-20, 79 inches tall with a ribbon tweeter above quasi-ribbon midrange and bass, replaced it at $9,200 a pair plus a $695 external crossover. The $1,500 MG1.6/QR, reviewed in January 1999, and the MG3.6/R were credited with a new level of dynamics and transparency for the company, and the 1.6 stayed in the line, unchanged, for about twelve years.

At a 2009 show Diller celebrated his anniversary with the company under a poster reading Made in America, Sold in China and said Magneplanars used 90 percent US-sourced parts. On December 30, 2009 Magnepan announced the MG1.7 at $1,995 a pair, the first model with quasi-ribbon drivers throughout: woofer, tweeter and a new super-tweeter above 10 kHz on one panel, with wraparound aluminum trim as standard. The MG3.7 of 2011, at $5,495 to $5,895, applied the same lessons to the 3.6, and the 20.7 that followed in 2011 and 2012 at about $14,000 gave the flagship a newly designed quasi-ribbon midrange with about half the mass of the 3.7's panel and a more phase-correct crossover. The 3.7i at $5,995 and the $795 DWM bass panel were reviewed in October 2014, the 1.7i followed, and the .7 appeared in 2015 at about $1,400. Magnepan declined to publish what the i revisions changed; its sales manager said blind panels had confirmed them. The Absolute Sound later named the 1.7i its 2021 Budget Product of the Year.

The 30.7 of 2017, four panels per pair and four-way, at $30,000, was auditioned at the factory and then taken on a North American dealer tour by Diller, more than thirty demonstrations in 31 rooms, which produced its adjustable midbass control for smaller rooms. The Absolute Sound named it 2017 Overall Product of the Year, shared with the Wilson WAMM Master Chronosonic. At the other end, the $650 LRS debuted at AXPONA in 2019, sold direct and through dealers, designed to give a buyer a pretty good idea of what to expect from the 20.7 or 30.7. That September The Audio Beat marked fifty years: Mark Winey, Jim's son and an electrical engineer formerly at NOAA, was CEO, Diller had 46 years with the company, and Jim Winey said it had shipped way over 200,000 pairs. The LRS+ followed in 2022 at $995 and took a Golden Ear Award from The Absolute Sound. On November 15, 2023 the MG2.7i revived the two series: foil bass and midrange on one sheet below a 40-inch true ribbon tweeter, the smallest Magnepan floorstander to carry one, at $5,995, with an upgraded 2.7x at $10,000.

Jim Winey died January 10, 2024, at 89; Magnepan's own notice called him its visionary leader and esteemed founder, and Mark Winey continued as CEO. The X Series was already under way. Magnepan says the upgrade launched first through its service department and about a year later in full production, with a dealer price chart dated July 11, 2024; it credits Mick Bucher as the X Series creator, and the first review, of the 2.7X, ran on December 9, 2024. Wendell Diller had left Magnepan by 2025 and was working with Danville Signal on a DSP-controlled open-baffle woofer for Magnepans. Reviews of the 1.7x in July 2025 and the 20.7x, at $30,000, in October 2025 followed, and Hi-Fi News gave the MG2.7i 88 percent in its August 2026 issue. Magnepan remains a private company at 1645 Ninth Street, White Bear Lake, with a plant of over 50,000 square feet, building every panel by hand, selling the LRS+ direct and everything from the .7 up through dealers, and still refurbishing most of the models it has made in 57 years.