Modelling the perception of percussive low frequency instruments in rooms

Howard, MHR

Abstract

Throughout the study of room acoustics, adverse effects and methods of controlling
and mitigating modal behaviour are a well researched topic. However, despite this, a
gap between objective metrics and subjective results is still prevalent, thus resulting
in a limited understanding of perceived bass quality.
Previous work has suggested a group of perceptual attributes that are useful in
describing the effect of room acoustics on the perceived bass quality, however an
objective link to the perceptual attributes has not been quantified. Furthermore,
the scope of previous work is mostly concerned with small listening rooms and rarely
extends to other cases, such as that found in live sound reinforcement.
Hence, this work is focused on broadening the understanding of low frequency
quality due to modal behaviour in rooms, through extending the scope of research to
include larger listening environments and single instrument excitation of the room.
To investigate the characteristics of low frequency quality, various kick drums
were auralised using an improvement to the modal decomposition model and were
then rated in a subjective listening test using the descriptive bass quality attributes.
From the results, the attributes were modelled through a novel approach using a
Random Forest model, utilising a combination of acoustic and MIR features.
It was found that the perceptual attributes of both Resonance and Articulation
were predicted effectively from signal features, however Bass Energy was unable to
be modelled with any accuracy. Use of feature selection algorithms revealed that
Resonance and Articulation attributes relied on temporal and decay based features,
such as early decay time and temporal centroid. This result further suggests the
importance of temporal modal behaviour when considering audible effects due to
low frequency modes. The outcome of this work supports the growing body of work
that the effects of modal density are not as important as traditionally thought and
is therefore applicable to both small and large rooms.

Citation

Howard, M. Modelling the perception of percussive low frequency instruments in rooms. (Dissertation). University of Salford

• Thesis Type: Dissertation
• Deposit Date: Apr 21, 2021
• Publicly Available Date: Apr 21, 2021
• Additional Information: Funders : Music Tribe UK
• Award Date: Aug 28, 2020