The Victor Talking Machine Company Makes the First Electrical Sound Recording

In 1924 Henry C. Harrison at Bell Labs developed a matched-impedance recorder, which improved the frequency range from the previous narrow 250-2,500 Hertz range of acoustic recorders to a wider range of 50-6,000 Hertz using the condenser microphone, tube amplifier, balanced-armature speaker, and a rubber-line acoustic recorder with a long tapered horn. This system was licensed to the Victor Talking Machine Company which used it in April, 1925 to make the first electrical recording of a symphony orchestra: the Philadelphia Orchestra conducted by Leopold Stokowski, performing 'Danse macabre' by Camille Saint-Saëns: 

The new system was sold in October by Victor as the Orthophonic phonograph capable of playing back acoustically-produced and electrically-produced records. It extended the reproducible sound range by more than an octave on the high and low end.