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I Need Help, Stat!


MarkKnapp

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I am building a custom shaped guitar with simple but slightly customized electronics. I've hand made the pickups. Strat style single coils for the bridge and middle, lipstick for the neck. I've positioned the middle pickup further from the bridge pickup and closer to the neck pickup (pictured). The neck pickup I have reverse wound and reverse magnetized, this is so I can flip into the in between position and get the jazzy tone I need from this instrument. I followed instructions and have my black wires soldered to the start of the pickup, and my white wires soldered to the end of the pickup winds. I run those white wires on over to my selector switch where I've followed this http://www.stewmac.com/freeinfo/Electronic...ams/i-3192.html diagram (this is what I followed basically for the whole wiring). I have three 250k pots: vol, and 2 tones, I followed the diagram for wiring the 5-way selector to the pots (pictured with mess of wires showing), plus I've run ground wires across the tops of the pots to the volume pot (might be visible in picture). I've run from the volume pot out to the jack (AND I've already tried reversing the hookup to the jack, still didn't work). My ground wires from the pickups are run down and soldered to the bottom plate of the volume pot; the ground wire from the jack is also wired there with all of them; then I have a ground wire running from all of them and then soldered and wrapped around one of the screws of my bridge (which is a recessed and trimmed arch top style bridge, and I use a bottom attached tailpiece). THATS what I've done for wiring.

the wires I USED:

From the pickups- the vintage clothy material covered wires

From the volume ground area to the bridge- the same vintage clothy wire type

From the volume pot to the input jack- for hot: the vintage clothy type; for the ground black 22AWG nonshielded (single core?) PVC coated hookup wire

from the 5-way to the pots: red 22AWG (same as above) hookup wire

from the 5-way to the other point on the 5way (shown in diagram): that same red hookup wire type

from the tops of the pots to one another: black of the hookup wire

pictures of this madness:

view of pickup setup and hard to notice bridge ground: https://www.t-mobilepictures.com/myalbum/ph...7c2d9a6bcb.jpeg

current setup of controls (L to R: tone tone volume): https://www.t-mobilepictures.com/myalbum/ph...b6ecce511e.jpeg

my hand and connections to 5-way switch from pickups: https://www.t-mobilepictures.com/myalbum/ph...422f96256e.jpeg

connection to pots as dictated by stewmac diagram: https://www.t-mobilepictures.com/myalbum/ph...28ad3353d6.jpeg

the guitar just to see: https://www.t-mobilepictures.com/myalbum/ph...8736a23c4b3.jpg

some symptoms:

when plugged into amp there is generally a lot of buzzing, much less buzzing when i have the neck-middle selected or the neck selected.

less buzzing when i touch the strings. Tapping noise when I tap on the pickups with my fingers. When I touch the strings and tap the pickups with a pick it makes no noise. and worst of all...

the pickups don't pick up ANY STRING VIBRATIONS AT ALL.

please someone help me!

-Mark Knapp

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I have trouble following a verbal version of a schematic, but this jumped out at me...

Tapping noise when I tap on the pickups with my fingers. When I touch the strings and tap the pickups with a pick it makes no noise. and worst of all...

the pickups don't pick up ANY STRING VIBRATIONS AT ALL.

Sounds like the grounds are not making it to the jack, while the hot IS making it to the jack.

But also...

I've hand made the pickups

Check your pickups with a multimeter. You'll get an infinite resistance reading if there is a broken connection. I would expect ~6k if the coils themselves are good. (Test them with the leads disconnected). The multimeter is also your friend in sorting out the no-sound problem within the circuit. You get no string sound, but you get tapping on the coils... without disconnecting anything, and with no cable plugged into the guitar, measure DC resistance between the tabs of the jack. You'll get 0 or infinite I bet... the answer may point us in the right direction.

Basically it sounds like your circuit isn't grounded. This could mean a missing ground connection, or broken leads within your pickups. I've destroyed a few of my handmade coils by not treating them gently. The place where you connect the 42awg to the leads is where my pickups broke. Test the coils out of circuit to see if they're damaged.

Edited by Geo
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Hi...

OK...because you appear to have made the pickups yourself (did you make the neck pickup also?) there could be a host of problems that could cause such symptoms. As it could be one or a combination of problems the best idea is to go through a process of elimination...

For instance...one that came up recently with a very well known commercial custom pickup builder and experienced luthier that I was involved with a project in was that the pickup was not magnetized! It took a week to discover that my complex wiring (that I built and tested here), the sustainer (that can often lead to problems) and all the rest were not at fault...there were simply no magnets happening...

Ok...so see if you can feel how strong the maget pull is on the poles if you put something metal on them and pull them off...preferably compare that to a working pickup...crude, but should give some indication.

The neck pickup I have reverse wound and reverse magnetized, this is so I can flip into the in between position and get the jazzy tone I need from this instrument.

I am not sure if this is a typo or you misunderstood the concept. Usually it is the middle pickup that is rwrp so that any combination with it will be noise canceling. RWRP does nothing to tone untill combined and the effect is purely for noise canceling. The inbetween hollowness of a strat is a product of the spacing between the pickups. With your closer middle pickup...it will be a different and unknown effect...but definitely not a product of the pickup winding or electronics.

OK...

So, elimination means...test each pickup to ensure it works...wire each one directly to a jack socket...if the guitar does not have strings on it (there are none in the photos) hold them upside down over a steel guitar.

Oh yeah...missed a step....have you tested the resistance of the pickups for continuity (no wire breaks, good connection to the leads, etc) with a multimeter?

As for the wiring...it looks like a typical strat...does your switch connections look like the lever switch illustrated? Ahh..ok, looking at the pic it would appear to be...

Right...one common problem is the tone controls...if you disconnect the tone controls and jumper them directly to a ground point (back of the volume pot) this might give eliminate the tones as a problem - or identify that as the source.

...

The immediate thing that strikes me of the symptoms is that...the pickups are not functioning properly...assuming you have tested their resistance...that the most obscure problem is that the things have failed to magnetize...however since you made them yourself, it is possible.

The more common thing that gets no sound out is the wiring of the output jack...but it is a li9ttle odd that nothing comes out...

hope that helps for a start...

pete

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HERES the scoop on what I've done since your responses. I got out my multimeter and I unwired the the pickups from the pots and I freed up the jack. For one thing, none of the pickups had any magnetic tug on anything (I dont know WHY, they are alnico V and I ran them through some pretty strong magnets a lot of times and very slowly). when I checked all the pickups with the multimeter, to my shock, I found that NOW only the neck pickup is showing any readings of resistance. Now i potted those suckers this summer, I watched them stop bubbling and then waited more, and afterward they were still showing on the multimeter. Since then I removed the vintage wires because I needed to put new ones on after cutting my guitar in half. I don't know why the new ones would work fine on the neck pickup but not the other two. Regardless, I moved on to attaching the neck pickups lead wires directly to the output jack! to see if maybe there was light at the end of the tunnel. i put a string over the pick up and plucked it; no sound. i reversed the wiring to the output jack and plucked; no sound. so NOW it seems my pickups have committed suicide AND nothing works. I'm a smart kid.. but I get NONE of this right now...

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Ok...so you have confirmed one of my suspicions...

Without any magnet strength...you will get no (or sometimes very little) sound. The material is Alnico, but they are sold un-magnetized. Have a look at the Stew mac instructions on doing this and see that you have got your magnets the right way around and that you are doing it as per the instructions...they need to be passed through a gap, it is not enough to stick a powerful magnet to the things for instance...

The most common problem is not that the wire breaks if wound successfully, but that the connection between the very fine winding wire and the lead/eyelets have a poor connection. Usually this is a failure to ensure that the enamel coating on the winding wire is striped off before soldering making a poor join that easily fails. This is of course very hard to do as the wire is so thin but necessary. Very fine sand paper or s a scrape is required, but you need to get it off both sides of the wire where it is soldered, not just barely enough to get a reading as there will be hardly anything to get a connection to.

If necessary, or if it breaks...you can wind a little off the coil and try again on the tail end. The inner wire though is the danger point as obviously you can not generally get a second chance to wind some off from the inside of the coil.

Wax potting can bring out faults also...the heat can loosen a join or re-insulate under a bad or incomplete solder join at the eyelet.

I know that these fabric covered wires is vintage spec...but really, it is wire and has only mojo benefit. The reason it was used in the fifties is because they didn't have better ~ you do! Ideally, you would use shielded cables...but this can lead to more problems with soldering if not experienced and with these fine wires...so avoid it.

...

Don't panic yet...it is recoverable I suspect...the only huge danger is the inner winding wirees...if this breaks close to the coil there is no return but to rewind the entire thing.

The magnet thing of course is crucial...so check out exactly how you were doing it and that the magnets are oriented the right way...if they were opposing each other for instance they will not magnetize anything.

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brief update, i just ran my neck pickup through magnets again, really really close, then hooked it up directly to the output jack. I got string noise.

The other pickups are still quite magnetic but non continuous. I will work on their continuity now, but I am concerned about the neck pickup not staying magnetized, i thought they were supposed to remain magnetized for years..

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There were breaks in the two single coils, i fixed those. The lipstick was unmagnetized, i remagnetized it. I tested all the pickups direct to the jack and they all worked. I wired everything up and it seems to all work (at least when i move the selector switch all the pickups still pick up sound). I don't know for sure if the pots are working as they are supposed to, but I do have them wired exactly as stewmac calls for. I've been testing them out of a really lousy pocket amp that buzzes a bit, but regardless they are terribly buzzy when it's plugged in. I'd prefer if my guitar could be quite silent when not being played, and essentially buzz free (as I will use it for jazz playing). From here how can I best achieve this?

Thanks for all the help so far, significant improvement upon how it was.

-Mark

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Well...you are behind the eightball with single coil pickups...

I put a new SCn Fender neck pickup in my tele (see link and sound clips in signature below) which is dead quiet...but it has two coils and central magnet structure for a humbucking effect.

Single coils are not traditional for "jazz" but jazz is such a broad genre....what do you think jazz sounds like?

Noise has become more of a bug bear for me though...a lot can be done with single coils if you completely shield the guitar...this might be hard to do with this one. A very good alternative is to use shielded cable. I mentioned this earlier but with problems already I didn't want to tempt fate. If you find some twin core shielded (two wires in shielded case) this can be better and easier. Connect only the inside normal wires to the pickup and connect the shield with one wire to the ground at the control end. This helps prevent ground loops and makes easier connections to the pickup itself...the shield may be more effective than cavity shielding for the length of the cable...

However...single coils are noisy...that's why they invented HB's. Some "stacked" single coils are better than others though tone wise and a lot of people swear by the single coil sound despite the noise. A RWRP inbetween combination should give you a fair amount of HB effect...however if you have made the neck pickup rwrp, then the bridge middle will not have an HB effect...not ideal!

Also...not sure you can do it with that switch, but neck and bridge is a cool sound not normally found on a strat...with a rwrp neck pickup you'd get some HB effect in that combination as well...

The other thing is the amp and lead...none of that helps if they add noise. Also, a lot of people don't realize how much noise their guitar makes because they use modeling units with a lot of noise reduction...

Anyway...a few thoughts...maybe too many...glad to see you have worked some of the problems out...

pete

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