ABSTRACT
This chapter focuses on audio frequency distortion mechanisms and analysis. Most measurements in the audio field involve characterizing fundamental parameters. The chapter explains the purpose of Audio Measurements, comparison of root-mean-square and average voltage characteristics and illustration of the crest factor in voltage measurements. Measurements are made on audio circuits and equipment to check performance under specified conditions and to assess suitability for use in a particular application. The measurements may be used to verify specified system performance or as a way of comparing several pieces of equipment for use in a system. The chapter describes response characteristics of several common weighting filters for audio measurements, illustration of total harmonic distortion measurement of an amplifier transfer characteristic and simplified block diagram of a harmonic distortion analyzer. Harmonic distortion measurements excite the device under test with a sine wave and measure the spectrum of the output. Harmonic distortion may also be measured with a spectrum analyzer.
