I think plant emissions are up in the like 40-80khz range? You can get consumer specialty mics that go up into the 50s for sure, but I'm not super well-versed o

I think plant emissions are up in the like 40-80khz range? You can get consumer specialty mics that go up into the 50s for sure, but I'm not super well-versed on the capture options in that freq range.