I've only listened for a couple hours with this thing, but it's a pretty sick design. My 92yo RF engineer grandpa basically laid it out over the phone the other day: "With the low noise ICs these days you could just..." I mentioned it while driving him to a doctors appointment and back, in my own autistic world so much I missed a turn........... but yeah it freaking worked without me really looking at it which is crazy, I'm going to dig into the design and change it up for v2, smaller board, potentiometer for gain instead of fixed low/high maybe some other stuff I haven't looked at yet. The more I think about it it's not that complex, but it seems legitimately "fresh": I haven't seen a design using an opamp on the front end, or really opamps anywhere really