I ran mini card Mics > battery box > line-in > JB3. W/O a Preamp, you can hear the hard drive spin in your recording. W/ Preamp, attenuation is bumped up, over-riding the HD noise. Therefore, if you don't use a AD20, UA-5, or higher, your recording will be bastardized by the beep that comes around every 20 seconds or so. Many people have experienced this problem until they threw in a a preamp. As for line-in vs digital, I went direct w/ digital. If you got it, use it. Sorry if I wasn't clear.