A recent study conducted by the ‘Hong Kong University of Science and Technology’ has concluded that MP3 compression significantly alters the emotional characteristics of certain musical instruments. We know from previous research that the unique timbre of a sound and the overall audio quality of music is altered by extreme MP3 compression. But what we did not know, until now, is that listening to compressed music can also alter our emotional response to it. So what emotions are affected?
In order to identify whether the emotional timbre of music is affected by compression, the research team selected 8 sustained instrument sounds for the basis of their research; Bassoon, Clarinet, Flute, Horn, Oboe, Sax, Trumpet and Violin. Using these 8 sounds the listeners were asked to compare four types of compression (None, 112Kbps, 56Kbps, 32Kbps) for each sound over ten emotional categories: Happy, Heroic, Romantic, Comic, Calm, Mysterious, Shy, Angry, Scary and Sad.
To put these levels of compression into context:
CD – 1411 Kbps
iTunes Download – 256 Kbps
Spotify (Non Premium) – 160 Kbps
Spotify (Premium) – 320 Kbps
So what did they find…1) Negative and Neutral emotional characteristics (Sad, Scary, Shy & Mysterious) increased with more MP3 compression. 2) Positive emotional characteristics (Happy, Heroic, Romantic, Comic & Calm) decreased with more MP3 compression. 3) Angry emotions were relatively unaltered. Demonstrating that whilst MP3 compression is convenient it is not necessarily the healthiest option – the fast food of the music world if you will. However it’s worth noting that the levels of compression tested were far more extreme than the market norms listed above. And therefore in order to truly understand the impacts of compression on emotional response we really need a study that focuses on more commercially applicable bit rates. That said it is fair to assume that any level of compression, is to some degree, altering music’s emotional timbre, and therefore as listeners and DJs we should always strive for the highest fidelity possible.
To read the full Research Paper click the link below:
[The Effects of MP3 Compression on Perceived Emotional Characteristics in Musical Instruments]