The Jones High Fidelity Audio Power Amplifier of 1947

Abstract

IN THE YEAR 1940, I designed and built a solid Jamaican mahogany-body electric guitar, which required a special type of audio amplifier design that would properly respond to particular guitar sound frequencies generated from a magnetic transducer. The amplifier should be portable, responsive, self-contained with its own speaker and cabinet, and be able to accommodate at least two instruments. It should be equipped with individual volume and tone compensating controls; not the high cut-off tone control commonly used in radio circuits of those days, which served to subdue static noises, but specially designed electronic tone compensating circuits. This type of amplifier required knowledge of sound engineering. There were no amplifiers commercially available at that time for the required purpose. Most superheterodyne radio receivers were equipped with two stages of audio amplification and were totally inadequate and unsuitable for the reproduction of an electric guitar. Although there were some high-quality radio receivers around, owned by people with ample means (the famous Scott thirteen-tube superhet receiver sold by Frank E. Lyons and Company of Lyons' Wharf in Kingston, for instance, used an output section of six valves in push-pull parallel circuitry, driving a thirty-inch electro-dynamic speaker weighing over eighty pounds, housed in a silverplated steel enclosure set on casters), such luxuries were not available to me for the simple reason that I could not afford them. I probed around for electronic literature, and discovered some audio circuit designs in electronic magazines, such as the British Wireless World, and the USA publications Radio Electronics and Electronics World. Using the information thus derived, I designed and, with some experimentation to avoid electronic feedback howls, produced a reasonable guitar amplifier of good response and fidelity.I produced an electric guitar and amplifier for Fitz Collash, guitarist and music arranger for the Milton McPherson ten-piece orchestra. I supplied the band of the USA Military Expeditionary Force stationed at Vernamfield, Sandy Gully, Clarendon, with a guitar constructed from Jamaican mahoe and satin woods, along with a compensated amplifier using power pentode output tubes. The same was done for Don Hitchman of the Red Gal Ring Sugar Hill Club in St Andrew with the exception of the guitar, which was an American Gibson hollow-body concert model that I converted to electric. As was done for Hitchman, the same was done for Victor Brown, guitarist with the Redver Cooke Red Devils dance band; guitarist Gladstone Taylor of the Roy White dance orchestra; Jellicoe Barker, who led his quartet doing hotel duty on Jamaica's north coast; and my own guitar-led sextet doing duty at the Silver Lining Club in downtown Kingston. My electric guitar served to bring me a sort of connoisseur status among musicians of the era.Later, when I volunteered for war service and joined the British Royal Air Force in 1943, my commanding officer would give me the privilege of constructing and using an electric guitar during my war service. On my return from the war in 1946, I did electronic guitar conversions complete with amplifiers for Keith Stoddart of the Sonny Bradshaw Seven, and Ernest Ranglin of the Val Bennett Band. Bennett was a comical tenor-saxophone-playing bandleader - in the tradition of the colourful American Cab Calloway, who visited Jamaica with his band and was featured at the popular Carib Theatre in Cross Roads, Kingston, in or around 1950. Bennett wore colourful five-shilling Jamaica Government Savings Bank notes as lapel bouquets. Ernest Ranglin's guitar-playing was a feature of the Bennett band as well as of the Colony Club band of 1951 led by Eric Deans (whose real name was Dudley McMillan). The devastating hurricane in August of that year put paid to one of my converted model guitars on loan to Ranglin.I must note here that there were public address systems commercially available in at least one electronics store in downtown Kingston. …