[oldeurope]

Hi, I made a parts description for you. Hope it helps understanding what is going on. The complete schematic followes soon.

Parts description for the dc coupled triode RIAA preamp 2007

R1 pick up load resistor
R2 RFI Filter resistor (optional)
R3 / C2 positive supply voltage smoothing
R4 kathode resistor cathode coupled amp V1 V2
R5 / C3 negative supply voltage smoothing
R6 / R10 kathode resistor V4 C8 bootstrap capacitor
R7 / C4 positive supply voltage smoothing
R8 bias resistor V2 V3
R9 / C5 offset voltage smoothing first stage
R10 /R6 kathode resistor C8 bootstrap
R11 coupling valve V4 bias voltage feed resistor
R12 / C6 RIAA timing components for RIAA Valve V4
R13 / C9 positive supply voltage smoothing
R14 / C12 positive supply voltage smoothing
R15 bias resistor V6 V7
R16 kathode resistor cathode coupled amp V5 V6
R17 / C10 negative supply voltage smoothing
R18 / R20 kathode resistor V8 C15 bootstrap capacitor
R19 / C11 offset voltage smoothing second stage
R20 / R18 kathode resistor V8 C15 bootstrap capacitor
R21 / C14 RIAA timing components for RIAA Valve V8
R22 coupling valve V8 bias voltage feed resistor
R23 / C16 positive supply voltage smoothing
R24 cathode resistor for current source V9
R25 / C17 negative supply voltage smoothing
R26 / R27 grid bias divider current source V9
R27 / R26 grid bias divider current source V9
R28 output series resistor (optional)

C1 pic up load cap (optional)
C2 / R3 positive supply voltage smoothing
C3 / R5 negative supply voltage smoothing
C4 / R7 positive supply voltage smoothing
C5 / R9 offset voltage smoothing first stage
C6 / R12 RIAA timing components for RIAA Valve V4
C7 bias voltage decoupling to kathode of V4
C8 bootstrap capacitor for coupling valve V4
C9 / R13 positive supply voltage smoothing
C10 / R17 negative supply voltage smoothing
C11 / R19 offset voltage smoothing second stage
C12 / R14 positive supply voltage smoothing
C13 bias voltage decoupling to kathode of V8
C14 / R21 RIAA timing components for RIAA Valve V8
C15 bootstrap capacitor for coupling valve V8
C16 / R23 positive supply voltage smoothing
C17 / R25 negative supply voltage smoothing
C18 grid bias voltage smoothing V9

V1 cathode follower, V1 V2 cathode coupled amp
V2 cathode input amp, V1 V2 offset voltage difference amp
V3 high impedance load for V2, kathode follower, plate voltage source for V4
V4 RIAA coupling triode
V5 cathode follower, V5 V6 cathode coupled amp
V6 cathode input amp, V5 V6 offset voltage difference amp
V7 high impedance load for V6, kathode follower, plate voltage source for V4
V8 RIAA coupling triode
V9 high impedance current source for V10
V10 low output impedance cathode follower, output stage

Thanks for looking,
kind regards,
Darius