Bought a Jazz with some wiring issues(?)

A

AdrianSD

Well-known member
Hi all, first time poster here :) Bought a Jazz SH2N from an eBay seller (Australian based, I'm in Australia) with the intention to replace the '59 in my MIM Charvel San Dimas. The white label on the back shows "28791 20170205 SH2N NECK". It came with complete packaging, although the box wasn't sealed (are the originals sealed btw?)
Looking at the wiring diagrams and the existing guitar wiring it seemed to be pretty straightforward, drop in replacement. Well, I was wrong, the Jazz was dead and I'm pretty pissed off I haven't measured the resistance *before* starting to unsolder the 59, remove it, solder the Jazz in and all that. Pulled it out and reinstalled the 59, all back to normal.
Then I started to measure the resistance between the wires and here are the results:
Red - White: 7.28K
Red - Green: Infinite
Red - Black: Infinite
Red - Bare: Infinite
Green - Black: 7.16K
Green - White: Infinite
Green - Bare: 7.17K
Black - Bare: 0 <--- Oops?
Black - White: Infinite
White - Bare: Infinite
Looking at the humbucker color codes attached in the photo these readings don't make much sense to me. Have I been sold a dud that's been tampered with? Short of pulling it apart to see what's inside, what else can I do? Already contacted the seller.
Thanks.
 

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I don't think you have a dud per se, but you've got one that someone has messed with the wiring. So, your two coils are now R/W and B/G instead of R/G & B/W. Put your meter on red & white, and on the lowest DC volts setting. Bring a screwdriver up against it, then yank it away. If the voltage is positive as you approach, and goes negative when you yank it away, then mark the wire that's on the red lead as positive and the other as negative. If you got the opposite, then black meter lead is positive and vice versa. Do the same for the green & black. Also, when you do that test, note which is the stud and screw coils.

Now, you should be able to connect them up properly and be in phase. And normally, the boxes are just held together with a piece of Scotch tap on either end.

If that didn't make sense, I can probably explain it better with pictures.
 
Excellent, that really helped, thanks! It appears that I have:
Red - positive
White - negative
Green - positive
Black - negative, also ground.
Comparing the results with the color codes image, how do I know which coil is which? Assuming the ground wire is connected to South start, this means Green & Black are the screw coil and Red & White are the stud coil, is this correct?
After connecting white and green the resistance measured between red and black is 12.2K. Is the reading right? Looking at https://www.seymourduncan.com/single-product/jazz-model page DCR is listed as 7.5K. Is the value per coil or for the humbucker when both coils are connected in series?
Sorry, so many questions from a noob, really appreciate your help :)
 
No prob. Simply put your meter leads on red/white. Do the screwdriver test on both coils. One will be very weak, or zero, and the other will have a decent reading. Probably in 20 - 30 mV range. The strong one is the coil that goes with those wires. Repeat for the other coil just to be sure.
 
Yeah. Those numbers clearly aren't right. I don't think you have a Jazz. I hope you didn't get cheap Chinese clone. How does the baseplate look?
 
Thanks everyone for chipping in, at least the learning curve is pretty steep, so at least I'm happy on this front :) Mmmm right, the readings are almost similar to the stock JB TB-4s I have in both Charvel and Jackson Pro DK2 guitars measured on the jack with the cable plugged in, for comparison the '59s are around 7.6K ballpark. Another interesting bit: the distance between the 2 outer pole centers doesn't match the regular, nor the trembucker dimensions listed on the SD site, it's kind of in between, around 51mm. While JB and 59s I have on the 2 guitars are pretty much dead on. It's a 5% tolerance, guess it's acceptable from the manufacturer's perspective?
Attached some photos, wondering if there's a way to spot a counterfeit?

L.E. Wrote to Seymour Duncan on the site's contact form about it too, see what they think about it.
 

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i dont have a duncan in front of me at the moment, but that looks questionable...the SD logo printing looks a little janky, and the back plate isn't the one they are currently using. also its upside down from the one in the pics i found here. now, any of these could just be a mix up, but if the wiring is wrong and it's reading 12k...it could be a counterfeit.
 

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Well, there is no question that you didn't buy an SD Jazz pup. Not even close!
But you bought it on ebay..."like a box of chocolates, you never know what you're gonna get".
I wouldn't even mess with it, return it. Ebay's policy should have your back.
 
They don't call it fleabay for nothing :) I have serious doubts the seller I bought the pickup off is an authorized dealer, what made me bite the bullet was the fact that it appears to be Au based, 15 years of presence and of course, the price! What should have been a read flag is the this seller only had about a dozen or so products for sale and the SH-2N are the *only* pickups for sale, in fact the only music related products, everything else is what, perfumes? Just looked now, they're down to only 4 products, 1 pickup and 3 perfumes. I mean, seriously, I should have known better :))
Speaking of price, down here we're being charged a big premium compared to US for a lot of goods, we call it Australia Tax and trying to find a good deal is somehow a national sport, almost as popular as the AFL. I paid on the pickup a ridiculously low AU113, which is really close to the price authorized US based sellers are selling it for. For comparison, a bricks & mortar store price is ~AU170.
Anyway, putting this behind now, I've initiated the refund already and now eyeing a Full Shred neck to go in the Charvel with a Duncan Distortion in the bridge. For the Jackson I've decided to experiment with a Custom Custom / Jazz pair. Don't know how this will end up, in a way I really like the trashy, nasal sound of the JB, it's nothing compressed about it, just open, happy sounding, in your face pickup.
 
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The Custom Custom and the Jazz is an interesting combo...you will get a clean and clear neck pickup with a huge swath of mids on the bridge. It should work great.
 
Thanks Mincer, looking forward to receiving the parcel with CC & Jazz pickups, still somewhere between HK and Melbourne according to Australia Post tracker :)) Think I owe everyone some updates. Just received a *genuine* Distortion SH-6B and compared it to the so called Jazz. Tell you what, the baseplates look identical to me, can't really see the difference. *But*: the pole spacing on the fake one is a bit off, between a humbucker and a trembucker and the cable feels very thin and flimsy on the fake compared to the Distortion and the other Duncans I have in my guitars, as if the shielding is thinner. DCR on Distortion reads 16.6K and the wiring is right, can't wait to pull up the soldering iron this afternoon and do the switcheroo :)
I'll also report back on how much of a difference I *feel* when using regular pole spacing in place of a trembucker. TB-4 swapped with a SH-6B.
 
Ok, got my money back and the fake Jazz is sitting on my desk now, ready to be dismembered. What should I do with it? Would a rewind done by a professional be able to improve the sound? It sounds really weak and has a lot of hum noise so shielding is a problem, combined with the messed up wiring sounds like an interesting project to take up.
Do you think it's worth trying to rewire? How can I gauge / measure the magnet's quality?
 
I think it might be fun to experiment with. Buy a few magnets, etc. But in the end, you got your money back so you have to decide if it is a project worth undertaking. It is at least a good refrigerator magnet, if not a good pickup.
 
i've used cheap humbuckers as a way to practice magnet swapping/hybrid making/just seeing how humbuckers work/etc etc.
 
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