The audibility of the temporal characteristics of audio systems

The characteristics of audio equipment are rarely studied in time domain, mostly in frequency domain. Although the characteristics in frequency domain are important, the primary way humans here sound is in time domain. The characteristics of an audio system in time domain should therefore be given more attention. In this paper, some common misunderstandings of the Fourier theory are discussed, explaining why the attention has shifted too much towards the frequency domain. The misunderstandings are illustrated by some paradoxes and these are used to direct the developments towards improved temporal response, based on the properties of human hearing. The improvements, which can be obtained, are illustrated with the application to pick-up cartridges, the CD-filtering, crossover filtering and compensation of a woofer in an acoustic box, both in frequency and time response. The application of this approach has resulted in audio systems, which are judged very high in natural sound by objective listening tests by many individuals. In the appendices, the basic calculation procedures to determine the temporal response of systems are presented, including the source code of a QuickBasic program to perform such calculations.