bridge pickup 4001 bass

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bridge pickup 4001 bass

Postby (yabbadehut) » Sun Oct 18, 2015 5:09 am

Dear all,

Glad i discover this nice forum.

Can i ask some advice? i have 2 4001 basses, one of them has a low output treble pickup ( bridge) the sound is softer and thin compaging with the other pickup and the one of my other bass. This one is a 1975 one the other i have 1977. What can i do to get it better? replace the pickup? but i have alreasdy seen a Original 4001 bridge pickup is difficult to find. a replacement? but than it is not Original anymore? i have heard also from re-winding? COuld it be a problem the ground wire seems not attached and no wassers aswell anymore. the srews are direct to the rubber underplate with ofcourse the springs between...could this be give this problem? If someone knows a orginal pickup for sale, please drop me a line.

Best Regards!
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Re: bridge pickup 4001 bass

Postby (Wiker) » Sun Oct 18, 2015 6:18 am

Maybe the thin sounding one have the .0047uF inline cap, which suppresses lower frequencies from the bridge pickup, while on the other bass that cap has been removed or bypassed. Have a look under the pick guard on both you 4001s.
In the first photo in this post you can see a turquoise .0047 inline cap (in a '70s bass this cap probably is yellow).
viewtopic.php?f=2&t=411108&p=821590&hilit=.0047#p821590
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Re: bridge pickup 4001 bass

Postby (yabbadehut) » Sun Oct 18, 2015 10:10 am

Dear Wiker,

Thanks for your repley, but on both basses are the caps removed....
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Re: bridge pickup 4001 bass

Postby (jps) » Sun Oct 18, 2015 2:08 pm

yabbadehut wrote:Dear Wiker,

Thanks for your repley, but on both basses are the caps removed....

Has anything been put in place of those removed caps?
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Re: bridge pickup 4001 bass

Postby (yabbadehut) » Sun Oct 18, 2015 2:36 pm

You mean the electronic inside? i can;t say because my luthier did that, but the output was before the cap was taken out the same in level with the bass pickup as without exept the sound is harder...
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Re: bridge pickup 4001 bass

Postby (jps) » Sun Oct 18, 2015 2:46 pm

Are you sure you are getting any output from the bridge pickup when it is solo'd? Your luthier must put a piece of wire in place of the cap or there will be no sound from that pickup.
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Re: bridge pickup 4001 bass

Postby (yabbadehut) » Mon Oct 19, 2015 2:46 am

Yes, there is output, but a thin sound and not loud....( if i only swtich to this pickup)
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Re: bridge pickup 4001 bass

Postby (jps) » Mon Oct 19, 2015 3:02 am

Has your luthier measured the DCR of the pickups?
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Re: bridge pickup 4001 bass

Postby (yabbadehut) » Mon Oct 19, 2015 4:14 am

Hello Jeff,

Measured thr DCR? Is it a stupid question if i tell you i do not know what that is...?
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Re: bridge pickup 4001 bass

Postby (yabbadehut) » Mon Oct 19, 2015 4:17 am

Too show you my basses. the Burgundy is the 1975 with the treble problem pickup..
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Re: bridge pickup 4001 bass

Postby (aceonbass) » Mon Oct 19, 2015 11:29 am

Measuring the output of the pickups would go a long way to diagnosing your problem. A pic or two under the guard of both basses would help too.
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Re: bridge pickup 4001 bass

Postby (jps) » Mon Oct 19, 2015 6:09 pm

What Dane said!

Measuring the DCR is simply measuring the DC resistance (Ohms) at the leads of each pickup. Simple to do, use the selector switch to "disconnect/turn off" each pickup, in turn, to measure the other one. This isolates the pickups from each other while you are measuring them.
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Re: bridge pickup 4001 bass

Postby (yabbadehut) » Sun Nov 06, 2016 10:08 am

Ok, the problem is finally solved. I did bought another 1975 pickup but let the original one rewinded, the spare one is now in the bass and working well, the rewind one is now spare...THX!
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