Problem with new Fender Original Precision pickup

[Jesse Lawrence]

Hello all,

I bought a used P bass not too long ago that came with a SD quarter pounder. I haven't really enjoyed the QP very much, so decided to get a Fender Original Precision pickup. I installed the pickup today, and unfortunately the output level of the pickup is extremely low. I know that the QPs are of course higher output, but I really don't think it's just the difference between the QPs which I'm used to and the standard output level of the new Originals. I would estimate that the output level of the Originals is at most 1/4 of the output level of the QPs (perceptually speaking). In addition, my signal is distorting big time. It literally sounds like I'm using an overdrive pedal. Note that I lowered the pickups quite a bit, and the signal was still distorting.

One more thing -- when I touch the pole pieces on the pickup, there is a loud noise which is at about what I would expect in terms of output level. So, the noise made when I touch the pole pieces is much louder than the signal the bass outputs.

I feel pretty confident with my soldering skills, so I don't think it's a bad solder joint. Furthermore, I reinstalled the QPs just to test, and they sound just like they did before, so it's pretty reasonable to assume that I didn't make a mistake in the wiring.

Did I buy a faulty Original pickup? I guess my question is, if I did have a faulty pickup, would I expect these kinds of symptoms (i.e. extremely low output and distortion)? Or should I reconsider the possibility that there is something wrong with the wiring and/or a bad solder joint?

Thanks for any advice!

 

[petrus61]

I can't speak for the low output/distortion, but the noise on the poles is normal with these pups and can be more or less cured with some clear nailpolish. I like to add a coat, let dry and add another coat. There are other ways to alleviate this but it's too much of a pita for me.

As far as distortion goes...I'm at a loss. These definitely should not be "low output" through a quality listening device. The EQ curve on them is very different from the QP's so might mean some knob tweaking at the amp, but low output or dist isn't anything I've experienced with them.

 

[Laurent]

Double check your wiring job and soldering points. A new faulty pickup is not impossible but unlikely.

 

[Eric_Allard]

I was planning to write a post on the very same thing but then saw yours so I may as well piggy back on it.

I have a American Standard Precision Bass with an Original Precision Bass Pickup. I've been playing this thing for ten or more years, but it wasn't until recently that I noticed the loud buzz if I touch the pole pieces. Since I've been playing this thing for quite a while, I can't help but wonder if the pickups have always done that and I hadn't noticed until now or whether something has changed. Are pole pieces grounded on a typical Precision bass pickup? Is this noise normal? I checked both my Jazz Basses and my Rickenbacker and they don't seem to do this.

With regards to the original question, I bought my Precision used and it came with a SD Quarter Pounder before I replaced it with the Fender Original. With regards to output, the QP is indeed a little hotter than the Fender Original, but the difference was not significant in my case. If anything, the Fender Original seemed a little louder in the mix because it isn't as scooped in the mids. With the QP, I found the output was all boom and clang, which got lost in the kick drum and guitars, respectively.

 

[Gravedigger Dav]

Be sure you didn't fry a pot or a cap during the soldering process.

 

[Hopkins]

If you reinstalled the QP,s and they sound fine, then reinstalled the Fender pickup and it is still low output and distorted, then I seriously doubt that it could be a soldering or pot issue.

If you have a meter, check resistance of each coil at the solder connection. If both coils aren't the same resistance, then the problem is in the coil. If they are the same resistance, check again at the wires to make sure the solder connections at the coil are good. I suspect you have a bad coil.

 

[Yahboy]

Share my opinion.

I give my pbass a vintage full cloth wiring, along with new CTS pot and jack.

After done, I found my 63pup output lower than before. First I suspect the new CTS pot with defeat.

And finally, I foUnd the jack white wire is touch the cavity wall which with shield ing painted.

 

[Jesse Lawrence]

Thanks, all, for your input.

If you reinstalled the QP,s and they sound fine, then reinstalled the Fender pickup and it is still low output and distorted, then I seriously doubt that it could be a soldering or pot issue.

If you have a meter, check resistance of each coil at the solder connection. If both coils aren't the same resistance, then the problem is in the coil. If they are the same resistance, check again at the wires to make sure the solder connections at the coil are good. I suspect you have a bad coil.

Hopkins, thanks for this advice. I checked the total pickup resistance, which is showing 11.4 k ohms (spec is 10.5 k). The treble coil is showing 6.2 k and the bass coil is showing 5.2 k. Obviously, according to the spec, they should each be showing around 5.2 k (given that it's a series circuit). Would this difference of 1 k in the treble coil cause the sorts of problems (very low output, and a distorted signal) I'm experiencing? I would think that it would just be a case of the treble coil being over-wound, and therefore it would just result in a hotter output on the treble side. Of course, I could be wrong, and if so, wouldn't mind being enlightened on this matter.

At any rate, it doesn't seem like I've got a short or an open in either of the coils. The question, now, is does an imbalance between coils of 1 k lead to the sort of symptoms I've listed? I'm going to go over the rest of the circuit, test the components, and make sure I haven't got any problems there. At the very least, this is turning into a good learning experience. Let's just hope that it doesn't turn out to be an expensive learning experience.

 

[Hopkins]

Thanks, all, for your input.



Hopkins, thanks for this advice. I checked the total pickup resistance, which is showing 11.4 k ohms (spec is 10.5 k). The treble coil is showing 6.2 k and the bass coil is showing 5.2 k. Obviously, according to the spec, they should each be showing around 5.2 k (given that it's a series circuit). Would this difference of 1 k in the treble coil cause the sorts of problems (very low output, and a distorted signal) I'm experiencing? I would think that it would just be a case of the treble coil being over-wound, and therefore it would just result in a hotter output on the treble side. Of course, I could be wrong, and if so, wouldn't mind being enlightened on this matter.

At any rate, it doesn't seem like I've got a short or an open in either of the coils. The question, now, is does an imbalance between coils of 1 k lead to the sort of symptoms I've listed? I'm going to go over the rest of the circuit, test the components, and make sure I haven't got any problems there. At the very least, this is turning into a good learning experience. Let's just hope that it doesn't turn out to be an expensive learning experience.

Were the resistances measured at the coils solder connection, and at the end of each wire the same?

I have seen damaged coils have almost correct resistance on the meter but have the exact symptoms you describe. I have a feeling what is happening is there is a bad connection on the coil reading 6.2k which is causing a higher resistance than it should have. Assuming that you bought the pickup new, I would recommend you exchange it for a new one.

 

[reddesert]

I don't think an imbalance between the coils would cause low output or distortion by itself if the coils each had good continuity. It sounds like either a bad connection (possibly internal to a coil), or a loose ground wire.

 

[Jesse Lawrence]

Thank you all for the discussion. I am pleased to report that the pickup was not faulty, and my p bass is now sounding fantastic. I can't say exactly what the problem was, because I completely took apart the entire circuit, cleaned up all the old solder, tested all components, and re-soldered everything with nice new wire. Given that the bass came with QPs, in addition to (oddly enough) tusq saddles, I think it's safe to assume that the previous owner used the bass as a bit of a mod platform, and the soldering inside really showed that. I'm guessing that the problem was likely a loose ground connection, as reddesert suggested.

Anyway, the circuit is nice and clean now, good solder joints with nice tidy wiring. And most importantly, my p bass is now putting out some serious vintage vibe.

 

[Hopkins]

Thank you all for the discussion. I am pleased to report that the pickup was not faulty, and my p bass is now sounding fantastic. I can't say exactly what the problem was, because I completely took apart the entire circuit, cleaned up all the old solder, tested all components, and re-soldered everything with nice new wire. Given that the bass came with QPs, in addition to (oddly enough) tusq saddles, I think it's safe to assume that the previous owner used the bass as a bit of a mod platform, and the soldering inside really showed that. I'm guessing that the problem was likely a loose ground connection, as reddesert suggested.

Anyway, the circuit is nice and clean now, good solder joints with nice tidy wiring. And most importantly, my p bass is now putting out some serious vintage vibe.

Its strange how one pickup worked and the other didn't after installing and re installing both with the same results both times. Gently wiggle the wires where they attach to the coil to see if you can get it to act up again. I would make damn sure the pickup is good before calling it finished.

 

[bassliner50]

I don't care what anyone says. Those Fender Original P pickups sound good!

 

[goff]

I usually check the pickup before a planned install by connecting the leads by alligator clips to an open end of a guitar cable and hold the pickup over the guitar facing the strings and strum somewhat to get an idea of the sound and if the pickups work. You can also use a screwdriver tip and gently tap the pickups to check

Your problem was a short, either the pickup terminals to the shielding or somewhere in the control cavity or your jack terminals or a cold solder joint. That you redid your wiring and the sound came back clean means the install overlooked discreet connection and isolation.

All part of the learning process.