Larry Hartke and Ron Lorman began developing aluminum cone drivers in the late 1970s. They their first products, an aluminum cone, free edge tweeter and a 2-way bookshelf system with an eight-inch aluminum woofer, under the Hartke brand name. Hartke revolutionized bass amplification in 1985 with the creation of a unique aluminum cone driver that produced a bass tone with broad dynamics. Since then, Hartke has introduced a complete line of bass gear, including amplifiers, cabinets and effects.

Source:Hartke website (14 February 2022)