My P-Bass has gone quiet.

[spider]

All of a sudden am having to use TWICE as much front end gain on my amp as I used to.
It's a '99 US Precision.
Strings are new, pickup height is cock-on and have checked out the electronics too...
Nothing broken, nothing dirty.
I like to think I'm pretty good at maintaining my own gear, but this has got me beat.
It sounds fine, in fact it sounds great, but the disparity in signal level with my other bass makes it difficult to change basses mid-gig !
Am I missing something ?

[Beedster]

[quote name='spider' post='162410' date='Mar 23 2008, 10:00 PM']All of a sudden am having to use TWICE as much front end gain on my amp as I used to.
It's a '99 US Precision.
Strings are new, pickup height is cock-on and have checked out the electronics too...
Nothing broken, nothing dirty.
I like to think I'm pretty good at maintaining my own gear, but this has got me beat.
It sounds fine, in fact it sounds great, but the disparity in signal level with my other bass makes it difficult to change basses mid-gig !
Am I missing something ?[/quote]

If it's a passive Precision, check your amp and cable, then your bass.
Chris

[spider]

[quote name='Beedster' post='162411' date='Mar 23 2008, 10:03 PM']If it's a passive Precision, check your amp and cable, then your bass.
Chris[/quote]

Yep, done that - in that order.
Just realised I posted this in the wrong forum, oops...

[Musky]

I had something a bit similar, where I plugged my bass in one day and found the bottom end seemed to have disappeared over night. After the sort of checks you seem to have made it turned out that there was a thin layer of a hard lacquer like substance on the jack socket. I've still no idea of what it was, but it took something a lot more abrasive than switch cleaner to shift it.

[The Funk]

It could also be your pick-up needing a re-wind. But seeing as it's less than 10 years old that doesn't seem likely unless it was exposed to some heavy magnets.

[Muppet]

Absolutely sure with the electronics that you've not got an intemittent short? Sometimes it's only with screwing down the pickguard and inserting a jack (thus pushing wires together) that these things happen. Happened to me a few times.

Other than that, there's not much to go wrong with Precisions so I'd check the pickups, swapping them out if necessary.

[spider]

Thanks for that guys.
Gonna rip the thing to bits today and see if I can get to the bottom of this.
Anybody know what the DC resistance of the pickup should be ?

[Musky]

About 10.5k I believe.

[spider]

[quote name='Musky' post='162578' date='Mar 24 2008, 11:48 AM']About 10.5k I believe.[/quote]

You're right Musky, and that's exactly what my multimeter tells me.
Wiring is OK but there's something funny going on with the volume pot - it doesn't short when full on.
So I thought 'I'll bypass it, I don't use it anyway'.
Did that help ?
Did it F##K.
I've bypassed the volume control and IT STILL WORKS.
This is some kind of witchcraft.
I give up.

[BOD2]

To completely bypass the volume control (and tone control) you'd need to remove ALL connections from the jack socket, then solder the "hot" directly from the pickup to the "tip" connector on the jack socket and the "cold" (or earth) from the pickup directlt to the "sleeve" of the jack socket.

If you leave any other wires connected to the jack socket it's possible the controls would still be connected in parallel and would still have an effect on the sound.

[spider]

[quote name='BOD2' post='162854' date='Mar 24 2008, 09:42 PM']To completely bypass the volume control (and tone control) you'd need to remove ALL connections from the jack socket, then solder the "hot" directly from the pickup to the "tip" connector on the jack socket and the "cold" (or earth) from the pickup directlt to the "sleeve" of the jack socket.

If you leave any other wires connected to the jack socket it's possible the controls would still be connected in parallel and would still have an effect on the sound.[/quote]

Thanks BOD2, I went back and checked what I'd done and sure enough, I'd missed a couple of connections.
Never fiddle about with your bass when you've had a few beers !
The upshot is : I've now got a much-improved sound but the output is still very low.
So I guess my pickup is shot.