BS.1387

The printable version is no longer supported and may have rendering errors. Please update your browser bookmarks and please use the default browser print function instead.

EAQUAL stands for Evaluation Of Audio Quality. It's an objective measurement technique used to measure the quality of encoded/decoded audio files. It acts in contrast to more the common place subjective testing methodology deployed using ABX and ABC/HR reference testing (frequently preferred by hydrogenaudio). It's part of the ITU-R recommendation BS.1387. Several tests have been performed using EAQUAL most notably using numerous AAC encoders to determine via a Pearson Correlation the linear relationship between human ratings and EAQUAL ratings. The results however using objective testing methodologies are still inconclusive.

Additional reading:

EAQUAL Sourcecode linux archive of c code used to implement EAQUAL provided by Gabrial Bouvigne.
EAQUAL Tools zip compression archive of the utility used to perform EAQUAL tests provided by Rarewares.