hybrid FX loop (tube and mosfet)

[fhn_lopes]

hey Guys! I have half of a 12ax7 unused in my project and I need an fx loop, so I gathered some info arround the net (very limited BTW) about the subject and designed a hybrid paralel loop using one IFR820 mosfet for the output buffer (send) and half of a 12ax7 as the gain recovery stage. The design is simple, calibrating is tricky though, that's why I used some trimpots for both IFR820 and 12ax7 cathode biasing.
Well, here's the schem, please let me know if I'm losing my mind or there's a chance for this to work.

Thanks!

https://imageshack.com/i/p9taduplp

PS: dunno why the board isn't able to determine the dimensions of the image....