Here a page which converts between distortion attenuation (what the test measures), and % THD: http://www.sengpielaudio.com/calculator-thd.htm

-30dB is 3% THD!

And to go back to my example. 0.2% THD is -54dB, while 0.02% is -74dB.

Last edited by ClubNeon; 09/16/09 07:47 PM. Reason: THD not TDH
Pioneer PDP-5020FD, Marantz SR6011
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-Chris