Shure's First Stereo Cartridges 

1958/1961. A comparison of Shure's first 3 Stereo Dynetic models. Shure had been making phono cartridges since the 1940's and while some other manufacturer's first stereo models were more of a trial and error process with wild frequency curve swings and thin sounding low frequencies, Shure's first models were a mature product with a fairly smooth frequency curve and a full, strong bass.