Passive RIAA

Hello all.
I have recently written a document about the most common passive RIAA network consisting of four components. In the document I have tried to derive in a relatively simple way a set of design formulas for the RIAA network.
The information can be found on the following site:

http://hjem.get2net.dk/herrmann/riaa.html

On the same site I have also put a spreadsheet. The spreadsheet shows the response of the RIAA network when specific values of the components are chosen. I have made two versions: An OpenOffice.org version and an Excel version. I have not been able to check if the Excel version works on english versions of Excel (mine is danish).
I hope somebody will find it useful.

Regards Torben