The Effects of Audio Processings on the Perceived Emotional Characteristics of Musical Instrument Sounds

The Hong Kong University of Science and Technology
Department of Computer Science and Engineering


PhD Thesis Defence


Title: "The Effects of Audio Processings on the Perceived Emotional 
Characteristics of Musical Instrument Sounds"

By

Mr. Ronald Kyle MO


Abstract

Musical instrument sounds have been shown to have distinct timbral and 
emotional characteristics, and when audio processes are applied to them, their 
timbral and emotional characteristics are changed. In this thesis, we 
investigated into how audio processes change the perceived emotional 
characteristics of musical instrument sounds.

We first investigated the effects of MP3 compression on the emotional 
characteristics of instrument sounds, which has not been explored previously. 
Our results showed that MP3 compression strengthened neutral and negative 
emotional characteristics such as Scary and Sad, and weakened positive 
emotional characteristics such as Happy and Romantic. Interestingly, Angry was 
relatively unaffected by MP3 compression.

For artificial reverberation, since our previous research has shown that the 
distinctive emotional characteristics in musical instruments can be 
significantly changed with parametric reverberation, we would like to see 
whether the parametric reverberation results can be applied to real concert 
hall reverberation, namely convolution reverberation, as well. We would like to 
know whether these changes in character are relatively uniform or 
instrument-dependent as well.

Our finding shows that convolution reverberation had more pronounced effects on 
the emotional characteristics compared to parametric reverberation, yet there 
was a strong agreement in the results of parametric and convolution 
reverberations. For investigating into the underlying instrument space with 
reverberation, our results indicate that the underlying instrument space did 
not change much with both parametric and convolution reverberations, in terms 
of emotional characteristics. It means that reverberation time has a remarkably 
consistent effect on the emotional characteristics no matter whether parametric 
or convolution reverberation was used. It is also a reflection of their deep 
underlying functional similarities despite their fundamentally different 
implementations.

In terms of applications, our MP3 compression study will give listeners and 
music streaming service providers some preliminary benchmarks for understanding 
the emotional effects of MP3 compression on music. For the artificial 
reverberation studies, the relatively consistent rankings of emotional 
characteristics between the instruments certainly helps each instrument retain 
its identity in different halls. Moreover, the instrument-independent behavior 
of concert halls is perhaps what helps distinguish a good music venue from a 
poor one. This can be an interesting avenue for future work.


Date:			Thursday, 3 August 2017

Time:			2:00pm - 4:00pm

Venue:			Room 2611
 			Lifts 31/32

Chairman:		Prof. Ajay Joneja (IELM)

Committee Members:	Prof. Andrew Horner (Supervisor)
 			Prof. Xiaojuan Ma
 			Prof. Raymond Wong
 			Prof. Richard So (IELM)
 			Prof. Ricky Kwok (Elec. & Elec. Engg., HKU)


**** ALL are Welcome ****