Audio equipment testing is the measurement of audio quality through objective and/or subjective means. The results of such tests are published in journals, magazines, whitepapers, websites, and in other media. Those who test and evaluate equipment can be roughly divided into two groups: "", who believe that all perceivable differences in audio equipment can be explained scientifically through measurement and double-blind listening tests; and the "", who believe that the human ear is capable of hearing details and differences that cannot be directly measured.