Dones's invention was to provide portable sound enclosures capable of high fidelity reproduction of low frequency sound waves without giving an audible indication of the direction from which they emanated. Dones's loudspeaker was marketed in the US under the trade name "The Octavium" from the early 1960s to the mid-1970s. The Octavium was utilized by several recording artists of that era, most notably the Grateful Dead, bassist Monk Montgomery, bassist Nathan East, and the Pointer Sisters. The Octavium speaker and Dones's subwoofer technology were also utilized, in a few select theaters, to reproduce low pitch frequencies for the 1974 blockbuster movie Earthquake. During the late 1960s, Dones's Octavium was favorably reviewed by audiophile publications including Hi-Fi News and Audio Magazine. Another early subwoofer enclosure made for home and studio use was the separate bass speaker for the Servo Statik 1 by New Technology Enterprises. Designed as a prototype in 1966 by physicist Arnold Nudell and airline pilot Cary Christie in Nudell's garage, it used a second winding around a custom Cerwin-Vega 18-inch (45 cm) driver to provide servo control information to the amplifier, and it was offered for sale at $1795, some 40% more expensive than any other complete loudspeaker listed at Stereo Review. In 1968, the two found outside investors and reorganized as Infinity. The subwoofer was reviewed positively in Stereophile magazine's winter 1968 issue as the SS-1 by Infinity. The SS-1 received very good reviews in 1970 from High Fidelity magazine. Another of the early subwoofers was developed during the late 1960s by Ken Kreisel, the former president of the Miller & Kreisel Sound Corporation in Los Angeles. When Kreisel's business partner, Jonas Miller, who owned a high-end audio store in Los Angeles, told Kreisel that some purchasers of the store's high-end electrostatic speakers had complained about a lack of bass response in the electrostatics, Kreisel designed a powered woofer that would reproduce only those frequencies that were too low for the electrostatic speakers to convey. Infinity's full range electrostatic speaker system that was developed during the 1960s also used a woofer to cover the lower frequency range that its electrostatic arrays did not handle adequately. 1970s to 1980s The first use of a subwoofer in a recording session was in 1973 for mixing the Steely Dan album Pretzel Logic, when recording engineer Roger Nichols arranged for Kreisel to bring a prototype of his subwoofer to Village Recorders.