After diggin through some old posts, I see this has been brought up before, but with no clear answer given. So put simply, What are the parameters for the loudness contours?

For example Is there a fixed wheighting and the loudness "level" just effects where the curve is flat? or is the contour flat at some fixed level and the loudness varies the wheigting? Is this outlined in the DSP spec (part number?) and what are the recommended parameters?

Here's a site with some brief backround info:
http://www.sfu.ca/sonic-studio/Equal_Loudness_Contours.html
http://www.sfu.ca/sonic-studio/Sound_Level_Meter.html

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