The sound generated by electric propulsion systems differs compared to the
prevalent sound generated by combustion engines. By exposing listeners to
various sound situations, the manufacturer can start understanding which
direction to take to achieve compelling battery electric vehicle trucks from a
sound perspective.
The main objective of this study is to understand what underlying aspects decide
the experience and perception of heavy vehicle–related sounds in the context of
electrified propulsion. Using a thematic analysis of data collected at a
listening experiment conducted in 2020, factors affecting the perception of
novel sounds generated by a first-generation electric truck are investigated. A
hypothesis is that the experience of driving or being a passenger in electric
trucks will affect the rating and response differently compared to listeners not
yet experienced with this sound.
The results show that the combination of individual preference and experience,
hearing function, acoustic content, time variation, signal stability,
load-dependent feedback, and situation-equivalent sounds affect the outcome. The
assessment and rating of quality and acceptance did not differ between battery
electric truck experienced listeners and first-time listeners in general. The
only driving condition clearly breaking this pattern was the auxiliary brake
condition, which, besides being significantly higher rated by novel listeners,
also stood out as the highest-rated and most positively commented driving
operation overall.
In conclusion, several combined factors affect the assessment of electric truck
sounds. Three identified aspects are removing disturbing sounds, making the
sound environment smooth and silent, and providing clear functional feedback.
Memory of the contextual experience is a key factor when assessing sounds from
driving operations. The expected difference between listeners with and without
experience with electric truck sounds will be minor unless there is
exceptionally high sound quality.
