Download Sound quality of an Augmented Reality Audio headset In augmented reality audio applications the user is exposed to a pseudo-acoustic reproduction of the real acoustic environment. This means that the surrounding sounds are heard through a specific augmented reality audio (ARA) headset [1]. Ideally the pseudoacoustic environment should be an exact copy of the real acoustic environment. The acceptability and usefulness of such a headset depends strongly on the overall sound quality of the headset. Especially if the headset is to be worn for longer periods of time in everyday life situations, the sound quality of the system must be sufficient. In this paper an introduction to the aspects affecting the sound quality of an ARA-headset is addressed. In addition, results of a listening test for the overall sound quality of a well equalized headset are presented.
Download An augmented reality audio headset Augmented reality audio (ARA) means mixing the natural sound environment with artificially created sound scenes. This requires that the perception of natural environment has to be preserved as well as possible, unless some modification to it is desired. A basic ARA headset consists of binaural microphones, an amplifier/mixer, and earphones feeding sound to the ear canals. All these components more or less change the perceived sound scene. In this paper we describe an ARA headset, equalization of its response, and particularly the results of a usability study. The usability was tested by subjects wearing the headset for relatively long periods in different environments of their everyday-life conditions. The goal was to find out what works well and what are the problems in lengthened use. It was found that acoustically the headset worked fine in most occasions when equalized individually or generically (averaged over several subjects). The main problems of usage were related to handling inconveniences and special environments.
Download Wave Digital Modeling of the Output Chain of a Vacuum-Tube Amplifier This article introduces a physics-based real-time model of the output chain of a vacuum-tube amplifier. This output chain consists of a single-ended triode power amplifier stage, output transformer, and a loudspeaker. The simulation algorithm uses wave digital filters in digitizing the physical electric, mechanic, and acoustic subsystems. New simulation models for the output transformer and loudspeaker are presented. The resulting real-time model of the output chain allows any of the physical parameters of the system to be adjusted during run-time.