OK, so taken to read the same way in & out. Those translate to 42.7dB and 42.6dB gain for your implemented circuit that says 43dB on simulation as you posted it. Excellent agreement to theory and between channels for a tube phono you DIYed and its valves matching you achieved. Results show that the problem is NOT in your phono build.
Check everything mechanical about cart setup, condition, and all wiring. You now even got 0.000V input offset about grid current besides proven correct gain for MM, no suspicion on the phono build is left lingering.
![WP_20150420_037[1].jpg](/community/data/attachments/439/439621-bb3dbb72acaee54ee41aec09c47294ba.jpg?hash=uz27cqyu5U)
Something mechanical, something wiring, including clips. Tighten what seems loose. Or the cart magnet has lost potency? The suspension softened and glides low out of the flux focus? Try 1g, 1.5g, 2g VTF. What happens?
If you just play a record and disconnect the RIAA and put 47k over the outputs of your player. That would give an idea if the PUP is ok or not.
Well that too. But to see what kind of signal it is outputting. A scope or a true rms meter over the 47k
I ment over output and ground on both channels and read the results. Sorry if I didnt spell it out.
I'm in love with MM Linn K9, a lot f information lost but a lot of soul gained, remembered when I introduced in the HI-FI world: 40 years ago listening Linn Sondek LP12 + Ekos + K9, Copland integrated amp with MM, Dynaudio 3 way stand speaker.