G Pultec filter with API 325 makeup gain question

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Coldsnow

Well-known member
Joined
Feb 6, 2005
Messages
296
Location
Ohio
I'm running the filter section from the Gyraf Pultec into a 325 line amp for makeup gain.  Should I use the 220n cap in place between as well as the 470 k resister going from + to ground prior to the input of the 325 card? 
Also, could I put a 10k to 10k line input transformer in between?
Thanks
 
The original solid state pultecs had a 1uF cap from the filter to the opamp +IN, and 100K in parallel with 10pF from +IN to ground.  20K feedback, no feedback cap, they had a resistor to ground, but I'd use a trimmer.  150uF output cap into an HS56 wired 250:600 backwards.  If you use a 2520 there's no need for a feedback cap or a DC blocking cap in the gain section.  There's a schemo around here somewhere, but I couldn't find it just now.
 

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