Controversy over RIAA curve
After some googling around, I discovered that there have already been debates over proper equalisation, RIAA and all the other curves used in the record-cutting industry in other sites.
There was much debate on the subject in The Absolute Sound a couple of years ago. To read the thread, click http://www.avguide.com/forums/adjustable-riaa-curves-necessary
Also, I found a very interesting website on a product called the REK-O-KUT RE-EQUALIZER. The author said you may sometimes find Columbia records with LP (Columbia's own curve) equalisation on one side and RIAA equalisation on the other side! To find out more click http://www.esotericsound.com/Electronics/REQ2MAN.pdf
Related posts: http://hi-fi-avenue.blogspot.com/2011/09/more-surprises-about-curves.html