A Method of Measuring Directly the Distortion in Audio Frequency Amplifier Systems
W. N. Tuttle · Journal of the Society of Motion Picture Engineers · 1932
The question of a suitable measure of harmonic distortion is discussed. The distortion factor employed is defined as the ratio of the effective value of the combined harmonic voltages to the fundamental voltage. A simple rapid method of measuring this ratio is described which has several advantages over earlier methods. Results are given showing the performance of apparatus for the application of this method to the testing of audio frequency amplifier systems.