Are you using a mic pre with the korg d8?
I'm running my mics thru a Boss DE100 Digital Delay unit, which is preamped suficiently to give the vocals the kick needed. I also utilize the on-board effects, ie. "Punch" vocal and edit the parameters. I lay down vocals using
a Beta 57, and I also like to use my EV457, which is great for back-up and harmony, as it really brings out a good bottom end. Pop screens on both mics.
I bought my first D8 when they came out, Canadian Price: "gasp" $1100
Second unit cost me $900 "ouch!!!"