Subjective Evaluation of Music Compressed with the ACER Codec Compared to AAC, MP3, and Uncompressed PCM

Table 6

Summary stereo image scores: WAV, MP3 192, and AAC 192 (n=63). A score of 1 represents narrow and imprecise and a score of 5 represents wide and precise noise and distortions.

Song	WAV		MP3 192		AAC 192
	Mean	SD	Mean	SD	Mean	SD
Uptown Funk	3.31	1.07	3.08	1.11	3.30	1.07
Elastic Heart	3.59	1.05	3.44	1.11	3.55	1.16
These Days	3.32	1.12	3.29	1.06	3.46	1.07
Heroes (We Could Be)	3.15	1.15	3.07	1.21	3.32	1.21
When the Beat Drops Out	3.45	1.12	3.47	1.14	3.47	1.17
Dangerous	3.38	1.15	3.49	1.15	3.28	1.07
GDFR	3.77	1.06	3.67	1.15	3.66	1.18
Doing It	3.33	1.16	3.34	1.07	3.41	1.21
Make Me Feel Better	3.86	1.00	3.85	1.10	3.75	1.12
What Kind of Man	3.36	1.14	3.39	1.04	3.34	1.11
Grand Mean	3.45	1.10	3.41	1.11	3.45	1.14