Here is a Nordstrand 3B-4a 3-band preamp that spent about 24 hours in my jazz bass. I didn't have knobs for it so I ordered the concentric knobs directly from Nordstrand (they are modified Fender style knobs just like he uses on his Nordy basses). While I was waiting for the knobs to arrive I took the preamp out, wired it up passive for a gig and decided I liked this bass passive (go figure). So the preamp went into a box with the new knobs in case I changed my mind. It's been long enough now where I can safely pass this along. Controls are: Vol/Vol stacked Tone (push/pull for active/passive) Mid (push/pull for frequency switch) Bass/Treble stacked New the preamp would cost $225 and the stack knobs were another $40. Selling for $220 shipped in the US. Cheers and Happy Holidays.