Vertically Cut Sound Records Recent Fundamental Advances in Recording and Reproducing Sound Using Vertical Undulations on a Disk

Vertically cut disk sound records possess important advantages over laterally cut records. In their use the recorder and reproducer have been greatly improved. ``Cathode sputtering'' has replaced graphiting of the wax and a non-abrasive final record has replaced the abrasive record of the past. The improvements which result are: Noise has been reduced 25 to 30 db. Volume range has been increased from about 25 or 30 db. to about 50 or 60 db. Upper frequency cut-off has been extended nearly an octave (to about 9,000 cycles). The playing time for a 12-inch record may be increased from about 4 minutes to at least 15 minutes. The life of the record has been tremendously increased. A more faithful reproduction has been obtained as a result of flatter frequency characteristics and less non-linear distortion so that sounds are more distinct, life-like, and clean cut. The results demonstrated are enhanced by the use of better microphones and better and, particularly, much more powerful amplifiers and loud speakers than have usually been used before or are now used commercially.