outdated methods produces audible artifacts in blind listening tests. A 2007 study showed no audio difference between CD quality audio and higher resolution audio. Joshua Reiss performed a meta-analysis on 20 of published tests, saying that trained listeners could distinguish between hi-resolution recordings and their CD equivalents under blind conditions. Hiroshi Nittono pointed out that the results in Reiss's paper showed that the ability to distinguish hi resolution audio from CD quality audio "was only slightly better than chance". See also Hi-Fi Loudness war Notes References Sound