By 1913 the cylinder recording market was left to Edison. The disc had steadily grown in popularity with the consumer, thanks especially to the popular roster of Victor artists on disc. Edison refused to give up the cylinder, introducing instead the Blue Amberol Record, an unbreakable cylinder with what was arguably the best available sound on a recording at the time. The finer sound of the cylinder was partly due to the fact that a cylinder had constant surface speed from beginning to end in contrast to the inner groove distortion that occurred on discs when the surface speed slowed down. Partisans of Edison also argued that the vertical cut in the groove produced a superior sound to the lateral cut of Victor and other disc competitors. Cylinders, though, had truly peaked by this time, and even the superior sound of the Blue Amberols could not persuade the larger public to buy cylinders. Edison conceded to this reality in 1913 when he announced the manufacture of the Edison Disc Phonograph. The Edison Company did not desert its faithful cylinder customers, however, and continued to make Blue Amberol cylinders until the demise of the company in 1929, although most from 1915 on were dubbed from the Diamond Discs.