Overview

Voice and speech quality assessment constitutes the main part of this work. It deals with the question of what listeners perceive from the mass of all the acoustic sound signals that are offered to their auditory system, which ones they select, which ones they cognitively process and how they assess them qualitatively and quantitatively. This process leads to an assessment of the perceived and experienced speech quality, addressing the following questions.

• What is quality?

• What demands are made on quality?

• What exactly is quality in the context of speech communication?

• What is generally voice and speech quality?

• Which aspects of the quality of speech can be identified?

• How can the quality of natural speech be defined?

• According to which criteria is speech quality assessed in specific contexts?

• Can the quality of speech be measured auditorily?

• Is speech quality always assessed in the same way?

• Which influential factors is the assessment dependent on?

• Can the quality of voice and speech be measured instrumentally?

• How can voice and speech quality be designed?

• What is the quality of artificial speech like?

• Which expectations are placed on the composition of artificial voices and speech?

• What handicaps are there when creating voice and speech artificially?

Relating to the field of speech technology:

• What does quality generally mean within the field of speech and communication technology?

• Are there conditions according to which the quality of speech technology systems should be assessed (speech quality versus system quality)?

• What demands in terms of quality are made of...