pluses and minuses? i pretty much get what's good about itb, .... but what are the drawbacks of passive summing networks ... ? why is passive summing not a good thing? and while i'm asking, when doing itb are you printing back into the same machine or are you doing a d/a - a/d to another recorder. if it's the second choice then what are you recording to? CDR? a second daw? how about a hi def stand alone thingie?