I see. I had only seen the schematic in the first post, and gathered that C5 and C19 must be the RIAA correction capacitors. Thanks for the correction.
No, both active stages in original Marsh preamp have flat FR (Fig.9 in his article), and RIAA eq is a RCpassives between (Fig.7).
Where should I measure voltages? In the second stage everything appears to be -+ 24 volts except in the output. Where should I put my probes, then I can report back.The circuit is exactly as shown in the pdf and transferred to an etched board.