Boss Geb-7 Bass Equalizer

It seems a bit odd at first; the bands are not the usual octaves. But they cover just what most of us need on bass. For those wondering why there's a 10K slider, harmonics (especially playing with a pick or using slap techniques) can easily extend well up the audio range.
The biggest problem most people will face is that there is so much control; a little goes a long way. This pedal can drastically enhance (or destroy) your tone.
I got a good deal through Reverb.com ; my pedal was new in an open box.
Either these don't have the problems the GE-7B units had with noise, or I got the bargain of the century.

Seven bands is plenty for most of us to get the tone we want. If you expect to play random venues with limited sound reinforcement, you probably want to add a parametric EQ to handle resonance peaks and troughs (boomy/dead spots).