Guitar Speaker History - Jensen, Celestion, Eminence and EV, 1924-2026 The loudspeaker is the final electromechanical stage of an electric guitar amplifier. Its cone, magnet, voice coil, suspension and cabinet determine how electrical energy becomes sound. Four manufacturers helped define its evolution. Jensen - Founded 1927, Chicago, USA Founded by Peter L. Jensen, the company became a leading American loudspeaker manufacturer. Jensen speakers appeared extensively in Fender and other American amplifiers throughout the 1940s-1960s. The P12R used a 12-inch cone and Alnico magnet, while the C12N employed a ceramic magnet and heavier-duty construction. Their differing motor assemblies, cones and power ratings produced distinct responses. Original Jensen speaker production ended in the late 1960s. Licensed manufacturing resumed in Italy during the late 1990s. Celestion - Founded 1924, England Originating in Hampton Wick, Celestion introduced its G12 loudspeaker in 1936. A reinforced guitar-speaker design developed in 1959 led to the T530 Alnico Blue, associated with Vox AC15 and AC30 amplifiers. The ceramic G12M Greenback followed in 1965. Early versions were rated at 20 watts, with later 25-watt designs becoming widely used in Marshall cabinets. Celestion’s controlled cone breakup and midrange response became fundamental characteristics of British rock amplification. Eminence - Founded 1966, Kentucky, USA Bob Gault established Eminence in Kentucky, initially manufacturing three 18-inch speakers daily for Ampeg. Eminence expanded into one of the industry’s major OEM manufacturers, supplying speakers for guitar, bass and professional-audio equipment. Its branded Legend series and Cannabis Rex demonstrate the company’s range of speaker designs. The Cannabis Rex employs a hemp-based cone for a distinctive frequency response. Italy’s B&C Speakers acquired Eminence in 2023. Electro-Voice - Founded 1927, Indiana, USA Electro-Voice developed professional loudspeakers emphasizing power handling, efficiency and durability. Its EVM12L became particularly important in high-powered guitar amplification. The modern EVM12L Classic features a 12-inch cone, ceramic magnetic assembly, cast-aluminum frame and edge-wound aluminum voice coil. Rated at 200 watts with 100 dB sensitivity, it combines substantial power handling with high acoustic output. What determines speaker tone Sensitivity determines acoustic output for a specified electrical input. Cone mass, stiffness and damping influence frequency response and breakup. Magnet strength, magnetic-gap geometry and voice-coil construction affect efficiency, electrical behavior and thermal capacity. The surround and spider control cone movement, while open-back and closed-back cabinets alter bass response and acoustic radiation. Wattage ratings describe power handling, not loudness. Magnet material alone cannot predict tone. A guitar speaker is therefore not merely an amplifier accessory. It is an essential component of the instrument’s complete electrical and acoustic system. Sources: jensentone.com/ celestion.com/ eminence.com/ products.electrovoice.com/

The History of Sunn Amplifiers, 1963-2026 Sunn Amplifiers originated in Portland, Oregon, from a problem encountered by Norm Sundholm, bassist for the Kingsmen, whose 1963 recording of “Louie Louie” became an international hit. As audiences grew, conventional bass amplifiers lacked sufficient volume. Norm’s brother Conrad developed a more powerful amplifier using Dynaco high-fidelity principles. Early designs employed ultralinear tube circuitry, substantial output transformers and large speaker cabinets. In 1964, the brothers established Sunn Musical Equipment Company. Operations expanded to Tualatin, Oregon, establishing Sunn as a manufacturer of high-powered amplification. 1965-1969: The ultralinear era The 100S and 200S became Sunn’s defining early amplifiers. Classic versions employed two 6550 or KT88-family output tubes, ultralinear transformers and substantial power supplies. Despite their numerical designations, these models were commonly rated around 60 watts, depending on configuration and measurement standards. Their engineering emphasized clean headroom, low-frequency reproduction and volume before distortion. Sunn equipment became associated with major touring acts, including the Who, Jimi Hendrix and Mountain. Leslie West helped establish the brand among hard-rock guitarists. 1970-1974: The Model T Introduced in the early 1970s, the original Model T departed significantly from Sunn’s earlier designs. Its four 6550 output tubes delivered approximately 150 watts through a powerful guitar-oriented circuit. Unlike earlier ultralinear designs, the Model T employed different preamplifier and output-stage architecture. The Model T became highly collectible among musicians playing heavy rock, sludge and doom metal. 1970s-1980s: Solid-state expansion Sunn expanded into transistor amplification with its Concert, Coliseum, Alpha and Beta families. The Concert and Coliseum names covered several configurations, including solid-state guitar, bass and professional-audio equipment. The Beta Lead and Beta Bass, introduced during the late 1970s, became especially influential. The Beta Lead employed solid-state gain circuitry producing substantial distortion without output-tube saturation. Its distinctive response attracted musicians associated with grunge, sludge and experimental heavy music, including Buzz Osborne of the Melvins. Sunn also manufactured speaker systems, including 2x15 bass cabinets, 4x12 guitar cabinets and larger multi-speaker configurations. 1972-2002: Corporate ownership Sunn was acquired by Hartzell in 1972. Manufacturing expanded, including operations in Williamstown, Kentucky. Fender acquired Sunn in December 1985, continuing amplifier and professional-audio development. During Fender ownership, Sunn introduced the 300T, a 300-watt tube bass amplifier using six 6550 output tubes. Fender discontinued Sunn in 2002. 2023-2026: The return of Sunn In 2023, Sunn returned under a licensing arrangement with Fender. The revived company began developing modern versions of historical amplifiers, including the 100S and 200S, alongside solid-state designs. The revived brand emphasizes American manufacturing and the Sundholm brothers’ engineering traditions. Sunn’s historical significance rests on pioneering powerful bass amplification, developing high-headroom tube amplifiers, and establishing solid-state designs that influenced generations of heavy guitar music. Sources: sunnamps.com/pages/history sunnamps.com/pages/faq namm.org/library/oral-histor… premierguitar.com/