Parasound JC3 Phono

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Before any details are argued over, let us come to understand the schematic as a block diagram. It is a 2 stage design with the high frequency EQ between the 1'st and 2'nd gain block. (1600 X .047uF) Then the second gain block equalizes the bass boost that is also necessary. This is essentially the same block diagram as the Vendetta Research, except that the Vendetta uses an OPEN LOOP transconductance amp instead of a high feedback op amp. The additional op amp sections add balanced output and servo control of the DC gain. Almost any low current fet can be used as an output offset, or it can be ignored, if you want. The circuit will work without it.
Dear Mr Curl,

From your schematic, the first stage is AD797 (the ones used in production could be LME49990) and the second stage is OPA2134. The reason for using AD797 for first stage can be, that it offers lowest noise performance for MC cartridge. But I don't know why you use OPA2134 for second stage. Is it because of results in listening test or another technical reason or just because of its low price?
 
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