SUBJECTIVE AND OBJECTIVE EVALUATION OF THE AUDIO VACUUM-TUBE AMPLIFIERS

摘要

The subjective and objective evaluation of five high-quality vacuum-tube audio power amplifiers is presented in the paper. As the reference, a professional transistor amplifier has been used. The subjective evaluation has been done by a team of judges, as well as using a computer-based psychoacoustic model in accordance with PAQM protocol. The amplifers' sound quality assessed by the listeners is consistent with the one evaluated with the use of the psychoacoustic model. It was found that the best sound quality is obtained by vacuum-tube amplifiers, the worse —by the reference amplifier. The results of subjective evaluation are inconsistent with quality assessed by measurement of objective parameters: all amplifiers have comparable quality but transistor amplifier is the best one due to the lowest THD+N level.