#2
Not sure on that one. It says that you can plug it straight to your sound system, but I don't know if it would work the same way. I play straight through a DI box at church, but there's no adjustments to the sound. I have conflicting thoughts on this. I don't know that I could plug my guitar (acoustic/electric) directly into the sound system which would, in theory, be the same as playing through just the preamp you have mentioned.

Wish I could be more help, maybe someone has a little more knowledge on this than I do.
#3
well DI used at your church would problem be fore running maintaining your signal integrity through that long stretch of cable from the stage to the board, im just wondering if this would do that
Where the hell did slide guitar go!?!
#4
I use one all the time with a sound hole pickup and it works great.
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