Valve Itch phono

1% each but anyway since you found a solution for the caps then find 0.1% resistors too and follow Kevin's mod for 600 Ohm source. But is everybody's gen as flat as the anti-riaa will be? A good sound card may more easier be.
 
Build your inverse Riaa in good tolerance first and then its usable both with gen and meter/scope as well as with sound card and Arta FR test. Then play with all and decide what's better more accurate or easier good enough method for your phono bench tests.
 
:up:

Salas is too much 0.47uF 200V FT3 for C4?
 

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It will probably let your speakers cones move more with disc anomalies and rumble. Depends on your TT and speakers damping. Unless your C6 and power amp input impedance make a stronger subsonic filter already than what C4 and R8 define.
 
My preamps have an input impedance of 100K.

Itch preamp 3.9uF & 100K Cut-off frequency fc = 0.4Hz
Itch 0.1uF & 820K Cut-off frequency fc = 1.9Hz
Itch 0.47uF & 820K Cut-off frequency fc = 0.4Hz

No good go higher than 01uF, using V-Cap coupling calculator.

Load Input Impedance (Ohms): 820000
Capacitor Value (µF) 0.1
-3db Frequency (Hz): 1.94
Optimal low frequency response (Hz): 19.41

If used 0.47uF

Load Input Impedance (Ohms): 820000
Capacitor Value (µF) 0.47
-3db Frequency (Hz): 0.41
Optimal low frequency response (Hz): 4.13

So no act as subsonic filter for frecuencies lower than 20Hz
 
This is how it simulates for response with anti-Riaa at the input, C4 0.1u, R8 820k, C6 2.2u, and a 20k output load (a dcb1 buffer pre with its 20k pot for instance)
 

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