Originally known as the Gretsch-DeArmond Fidelatone (a real mouthful), the DynaSonic single-coil was the Gretsch standard pickup beginning in the late 1940s. DynaSonic pickups were among the first to offer individually adjustable polepieces, and featured glossy highs and tight bass response. According to Gretsch literature, “DynaSonic Pickups Yield a Tone of Incomparable Power and Fidelity!” In 1957, the Filter’Tron “Electric Guitar Head” was introduced at the Summer NAMM Show in Chicago. These were true humbuckers and by 1958, they had effectively replaced all the DynaSonics. The use of the word “head” rather than “pickup” was most likely Gretsch trying to make their specific design seem different or better than others.