Help!! Fender Jaguar bass seemingly possessed...

HAdam

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Jun 24, 2016
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Long Island, NY
I've got an early 2000s CIJ Fender Jaguar bass, all stock. It features an active passive circuit that is powered by a 9v battery. All was going well until last weekend I showed up to band practice and was greeted with an ear piercing shrieking coming from my amp. After some trial and error I narrowed the issue down to my bass (whether it was in active OR passive mode). What seemed so strange about this to me was that upon removing the 9v battery and switching to passive mode (bass is silent when in active without a battery, was always like this) the shrieking stopped and I could play it like normal. When I got home I tried a new battery but no luck. I haven't attempted any mods, dropped the bass (to my knowledge) or even opened the thing up in the past few months. I'm stumped! Any suggestions are welcome, please help this poor fool!
 
I had something like that happen with a loose connection once. I never did figure it out, it just stopped on its own. Good luck.
 
I had something like that happen with a loose connection once. I never did figure it out, it just stopped on its own. Good luck.
I thought you had the right idea, so I opened it up and compared every connection to the wiring diagram. Everything checked out so I'm thinking the pre-amp is fried, in which case I'll need a new one. Anyone got any suggestions?
 
Preamps are as individual of a choice as preamp pedals, pickups, even the bass itself.
Me, personally, I dig me a John East U Retro every time. They're solid, give you a variety of tone options, including a mid sweep in most cases, and can give you basic operation if you unexpectedly run out of battery.
The new ones are even more tweakable because they have internal trim pots.
There are lots to pick from. Best Bass Gear.com is a good place to start looking.

Hope this helps!
 
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Indeed, I believe your preamp is toast. I had the very same issue in a "Jazz Bass Plus" that I owned. I took it to a tech who opened it up and showed me a small burn mark on the circuit board. It was a really, really sad day because I adored that bass, and it was long out of production by the time that happened, and there was no replacement preamp that would equal it.
 
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I thought you had the right idea, so I opened it up and compared every connection to the wiring diagram. Everything checked out so I'm thinking the pre-amp is fried, in which case I'll need a new one. Anyone got any suggestions?

Fender probably can set you up with a stock preamp replacement. Their customer service folks are super nice and helpful.

Good luck.
 
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