"Andreas Bick, composer and sound artist based in Berlin, Germany, writes about sound related things (forgive wrong spellings and twisted grammar). Silent listening is about the fringes of music, the periphery where music turns into sheer sound - concrete, wild, sometimes stunningly beautiful. Visit me at www.andreas-bick.de and facebook"
3M's E-A-RCAL Acoustical Laboratory, established in 1979, has offered contract testing since 1992. The principal service offered is the measurement of the real-ear attenuation at threshold (REAT) of hearing protection devices (HPDs). Additional services include objective hearing protector and earphone measurements utilizing either KEMAR or the ANSI S12.42-2010 or ISO/TR 4869-3 acoustical test fixtures, or miniature microphones and/or probe microphones placed in real ears.
B. Moore. (2003)http://www.amazon.de/Introduction-Psychology-Hearing-Academic-Press/dp/0125056281/ref=sr_1_1/028-2148841-5385328?ie=UTF8&s=books-intl-de&qid=1193846958&sr=8-1.