I am the happy owner of a National Tri-cone. Not a vintage, it is brand new, but with a National pickup and a Baggs preamp it has an excellent sound. Still, can it be even better? I have seen people playing such a guitar with both a pickup and an additional microphone. Any knowledge about what kind of microphone to use? I think the idea with an additional microphone might be to pick up the crisp sound directly from the strings?