Ampeg Classic Analog Bass Preamp

I purchased this preamp in order to use it as a "color" effect. I hoped it could give some warmth to the sound of the bass. Kind of a bass/low-mids bump and some hints of tube character. I can't get that out of this one.
I use active basses, so as it is the case with other pedals, the pedal was clipping at unity gain. Luckily there's a switch inside the chassis that gets the input signal to -15db.
With that engaged, to keep unity gain every knob must be pretty much full on. In such case the signal seems to be boosted in its own entirety, with very little characterization.
The alternative is to sculpt the sound with a mid scoop and bass+treble boost.
In this latter case the sound is pleasant; still on the treble side some digital distorsion can be heard with strong peaks (ie slapping).
So this pedal is not for everyone.
Construction quality is excellent and the pedal seems to be made to last.
I'd say the bass control here is the most powerful between the three bands.