This is a wonderfully simple and effective device if used properly. First off you have a volume / gain control, then a three position switch that has a shallow notch, a step notch and a flat setting - and then a sweepable frequency control.
I go from bass with active EMG's into the NE-1 with gain adjusted to match my basses output and the freq around 2-3 on the dial ( you'll have to find your setting). If using a shallow notch you get a nice piano bass sound. In the deep setting you get a wonderfull full low end that is tight and just blossums.
You will find that in the flat setting it is as good as if it had true bypass.
Currently I go from the Ne-1 into a a B-max preamp. The combination is very nice due to the warmth created by the loading at the front end.
If I turn down the treble on my P-bass it's a buttery low end that is to die for. Crank up the tone on the bass and its Squire Geddy heaven.
You can find them used and they are hard to beat for the bucks.
I have recorded from bass into it - into the board with great results. Batteries last forever.
If you understand parametric eq and appreciate transparent but effective eq you will love this quality piece of gear.
Simple is good for you!