DUAL AUDIO: EFFECTS OF VOLUME RANGE ON DICHOTIC LISTENING VIA SPATIALLY SEPARATED SPEAKERS
Author: Steven J. KERR, Carmen SIAU
Abstract:Professionals who utilize communication devices may have to listen and monitor multiple audio streams whether from different Land Mobile Radio (LMR) or public broadband (LTE) channels whilst carrying out their day to day tasks. Understanding how humans cope with multiple audio streams is therefore important to help engineers design solutions that will allow professionals to both hear and understand vital information from numerous sources. This paper describes a usability study of a spatialized dual speaker system (one speaker on each shoulder) whereby 16 participants from age 23 to 54 had to listen to 2 audio streams played simultaneously, a primary audio stream on one speaker to be concentrated on to understand content and a secondary stream played on the other speaker to be scanned for keywords. Participants were asked true or false questions on the primary stream to gauge level of information understood whilst being scored on their ability to recognize when selected keywords were spoken in the secondary stream. These audio streams were played at different volume ranges and deltas to understand if differences in volumes across a range of volumes can assist users in this task. The results has shown that there does not appear to be a specific volume range or delta that assists users in listening to content from 2 spatialized audio sources and that individual capabilities are more likely to be an important factor. Devices that have capability of broadcasting multiple channels therefore need the ability for each channel’s volume to be controlled individually and not be auto changed, as each user will have their own personal preferences.
Keywords: Dichotic Listening, Multi-Stream Audio, Divided Attention