Aguilar OPB1 problems

[Pietzsa]

I need some help guys. I've had a Spector NS4CRFM for about four years now with the optional factory installed Aguilar OPB1. My problem is that no matter what I do I have a very loud 4K-10K constant ring when I plug in my bass. I've changed batteries, cords, amps, and nothing changes. I've even gone in the bass and cleaned up all the solder points and checked for correct voltage with a meter.

I don't want to ship the bass to Spector because of the cost, even though they would fix it. I've contacted Aguilar and they gave me some suggestions on troubleshooting, but all to no avail. The other thing is that I do get some bass sound out of it and the ring is still there even if I turn off the pickups. As long as the bass is plugged in, the ring is audible. Anybody have similiar problems or know what this could be?

[luknfur]

FWIW:

Did Aguilar suggest the pre may have gone south cause that's sounds like a strong possibility.

Interesting Spec would cover it after 4 years.

I'd make an accurate diagram of the wiring and run the pups straight to the jack. If no issue then has to be in the harness and never heard of pots causing ringing. I don't know what's in the harness but can't be much for an OBP-1.

Understand about shipping - probability of damage/loss let alone cost of shipping.

If the harness is indicated then I'd probably wire a passive harness and check it out. I had an OBP-1 in a bass with SD hot P/J stack and it sounded exactly the same with or without the pre so I sold the pre. You could pick up a used OBP-1 for about $50 and drop it in to verify the pre's bad. If it's not just resell it for about what you paid.

A buddy sent me a NS4CRFM when I first started playing bass cause he was pretty impresed with it. Had active EMG's in it and I had an Ibanez GSR 200 with EMG's and a BTC at the time and they sounded so much alike I just sent the Spec back. Heavy bass too.

[Pietzsa]

Oh no, Spector offered to fix it but not for free. All electronics on it were warrantied for only one year. Aguilar said they don't think it's the preamp because the failure rate is so small on all OBP's. I tried taking out the preamp, routing the EMGS straight to the jack and the pickups work fine without the noise. I wired everything back up with the preamp and back comes the ringing. So now I'm betting its the preamp that failed. What is an indication of a failed pot or bad grounding sound like?

[luknfur]

FWIW:

poor grounds produce a static/buzz quality that is commonly altered by touching grounded items - pots, strings, bridges, pickgaurds, etc.

Pots typically produce either scratchy tone when turned (if dirty) or confusing audio alterations (if miswired) - along the lines of strange tapers or being unable to tell a tone from volume. At any rate, they're usually isolated by manipulating the pot that's the source.

If your bass seems possessed by unexplained phenomenon, it's likely the pre.

Aggie is right, they rarely malfunction till they get about 10 years old but it do happen.

I don't think you mentioned playing another bass or guitar through the signal chain (amps, cords, etc.). There's all kinds of wierd stuff in the environment that could create issues.