1st Pleiades attempt of RIAA equalisation immediately after the cartridge

It works but takes noise considerations to limit. Signal path: I've had the time of my life from Dirty Dancing LP soundtrack - Technics SL1200 MK2 - Stanton 680 with low output D6800 EEE-III A&R stylus - 33K series 2K7 series 100nF series to gnd - 28nF from 33K to gnd and signal taken from 33K (inacurate network just used for a first impression) - directly to Realistic Disco Mixer mic in or to Pleiades Siemens AC151 open base pre or to Pleiades V6 1H4 open grid pre both feeding Realistic Disco Mixer at mic in - Sennheiser HD580 - listener's brain if any. When RIAA network directly connected to realistic mic in VU needle barely, barely moves but sound is nice smooth dynamic with nice deep bass and extended treble. When the AC151 is connected needle goes crazy, there is hiss at low passages, sound is nice but RIAA inacuracy may be taking place. When Pleiades V6 1H4 is connected more RIAA inacuracy is apparent possibly due to input and output transformers interplay with (V6 1H4 starved heater , plate voltage condition for low noise) input and output impedance in order to make flat frequency response to listener's brain when mic is used at soft voice, sound is more clear but less perhaps interesting with some hiss but less than the AC151. No input transformer should be tried too. Perhaps it might be better to do half of RIAA after the cartridge or all RIAA after the open base or open grid front end. Hiss would be inaudible but there may be overload of open grid base. 1H4 should be fine and after it a volume control should be a good idea to avoid peak overload of 2nd stage. Mic pres have to cope with a thousands times more dynamic range live signal anyway. The original Walter Le Pacific with 2SK170 should be tried.