Preamp in the Marcus bass

FWIW:

I can't tell if you're wanting to change the pups, preamp, or both.

The complaint is usually about the passive mode of which there's a fix in MM reviews in harmonycentral. But that does't sound like your complaint.

Had a couple/three of those pre's but can't remember what they look like. If the pot seperate there's no reason I'm aware of you couldn't use them as tones in a passive harness.

If you're going to Jetison the pups you can toss them my way. Don't want the pre but a package deal may be an option depending.

 

FWIW:

the Miller pups ARE passive already. The bass is only active because it has the preamp. You can't have a passive option in a bass with active pickups becuase active pickups have a preamp built into them that you can't access without destroying the pickup.

I don't recall what the pot value's are in the MM's but typical single coil passive pups use 250K pots. If that's what they are you could use them as tones.

HOWEVER, you're really better off leaving the preamp intact and set it aside and put in new pots/jack cause you're talking chump change. If the tech doesn't have the parts on hand they usually order every couple weeks so not a long delay. It's not worth it to chop up the old pre for the savings. The pre is worth something intact but pretty worthless chopped up - especially if at some point you want to sell the bass in it's original state which is how most guys would want to buy it.