I've done the tennesse thing, and I usually let the alcohol and sugar charcoal sit together for a coupple of hours, and then run everything through a funnel and coffee filters. Be carefull with the tenn, whiskey process, as you can end up "smoothing" all of the flavor out of your hootch.
As for sitting on wood, go by taste and color. Everything depends on the condition of the wood, the temp, and the proportions of the spirit to wood.
UJ's sour mash method should not need a tenneseee treatment,as there is no rye in the mash bill (just my opinion...it is a matter of peresonal taste).
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