The Phantom wrote:

The image Orig.png is the schematic of the originally published network.

The image T4_3_18.PNG shows the values when T4 is changed to 3.18 uS.

InvRIAA.png shows the formulas in pretty print.

I have a recollection that such a network cannot ever produce a true RIAA curve.

Lipschitz discussed this in depth in the AES journal about 30 years ago.

Graham