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I used a test record, an impedance bridge, and a lot of reading of manufacturers data. I wasn't going to use a transformer for matching, and the preamp I constructed had about a 100k input impedance. Using the cartridge manufacturer's data as a starting point, it seemed in my particular case that the cartridge wanted to see about 100 ohms x 1.5mf sort of additional load. This made for the flattest response. I am by no means an expert in this area, and since LPs are only a casual interest to me (tape is my thing), this is only an approximation at best. There are limits to the parts values at hand for the 'cut 'n try in my case. The loading networks were tacked directly on to the input terminals of the preamp for each try. -----Original Message----- From: Association for Recorded Sound Discussion List [mailto:[log in to unmask]] On Behalf Of Andrew Hamilton Sent: Tuesday, August 26, 2008 6:09 AM To: [log in to unmask] Subject: Re: [ARSCLIST] RIAA EQ software How did you modify the load as seen by the cartridge in order to make the ADC "look" like an ideal phono preamp's load for the chain? - a y-cable with a resistor on the unused end, so that the combined Z (of the ADC and the resistor) equaled the output Z of the cartridge? Or by some other network? Andrew On 8/26/08 1:42 AM, "Scott Phillips" <[log in to unmask]> wrote: > The loading of the cartridge was one of the first things I checked out. > As a cartridge is obviously a coil of wire (an inductor) and has > capacitance, nothing could even start to be right without setting up > proper loading for the particular cartridge.