I'm still a little confused on how and why you do that.
I run the vocal into the P.A. set the Treble -Mid-bass and reverb on head, then run the mic from the speakers into the Zoom, the main reason for it is a lot easier FOR ME to dial in the the sound I want 1st---- instead of goofing around with all that EQn--Effects-and all that other stuff. I want to hear the voice I am recording, not a dry run, that I might be able to duplicate. It takes a lot of the guess work out of first instead of last. --it also makes the song a lot easier for me to sing because it gives me more confidence to go to different vocal ranges and phrasing.
I mic the speaker with the Sm-58 several feet behind me, then do the vocal on the SM-57-facing away from the speakers, not much of the sound is coming from the speakers that gets to the SM-57. It's like playing live in front of people vs. playing in the recording room.
I am not all that great at that digital recording thing, if I had the skills like a lot of you guys on here I would probably do it, but I run low on patients when dealing with things I don't know much about,. I like just getting up there and singing the song the best I can---which ain't all that good, more times than not. --You heard my 1st vocals on "Hard Times" pretty damn corase, once I run through the P.A. head It gave you something kind of workable.
That's about the best I can explain it. Maybe some other Blues Brothers are having same problem as me and might want to give it a try. Got nothing to lose.. Later.