Scott Phillips wrote:
>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.
>
Capacitor in the bridge - now that's getting fancy. I should have
thought that resistance, alone, was the issue. I wonder if my "flat"
transfer would have gone better had I used a y-cable between the phono
and the ADC, with the other end going into the normal phono preamp?
This way, I could hear the record play, for confidence, from the preamp
without having to listen to the non-de-emphasized version playing,
shrilly, into the ADC, and the (ideal) input Z of the preamp would be
summed with the (lower) input Z of the ADC (I was using) to make a
nigher-to-perfect load, as seen by the cartridge.
Andrew
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