fixing a vintage Gold Foil pickup
As some of you know, my girlfriend and I moved from San Francisco, CA to Nashville, TN in May 2015 to be closer to a vibrant music scene and to start a new life in The South. The move was so exciting as we took a two week road trip across the country. You don’t get many chances to pick up and move to a new place so we took advantage of the opportunity. Becca started a blog called the Bay To River Rambler and you can see her photos and writings here.
We found a place in East Nashville with a standalone garage that I converted into a workshop and now I have more space than I know what to do with! I built myself a 2×8 workbench and got a drill press and now I am up and running. The pickup winder is all tuned up and I’m cranking out pickups again, ready to get your guitar tone in tip-top shape.
Things to look forward to in July:
Gold Foil release July 4th I’ll be releasing a brand new pickup based on the originals from the ’60s. I designed mine to be on the more affordable side compared to vintage or reissue pickups by other manufacturers and still embody that twangy, low-fi character. They will fit in a standard humbucker rout and start at $90 each.
Summer NAMM in Nashville July 9th, 10th, 11th I’ll be there walking around, checking out the exhibits, and meeting as many people as possible. I won’t have a booth this year, but I’ll be staking it out for future years. Check out https://www.namm.org/summer/2015 for more info on how you can go.
Humbuckers are essentially two single coils, side-by-side, wired in series (out of phase to “buck” the hum). One cool feature is that you can split the coils and use them as true single coils to get a brighter, cleaner sound. I say “split” the coils instead of “tap” the coils because that is something different entirely that gets confused often. Coil “tapping” is having multiple leads going to the same coil to access different output values. In order to “split” your coils, you must have four leads (five, including the bare ground wire). Here are some common humbucker color codes:
By connecting the South finish (-) and North finish (+) you have both coils wired in series with South start (-) connected to ground and North start (+) connected to the volume lug or the switch. The wiring diagram below shows how to wire my Apex Humbuckers to a switch like a push/pull potentiometer to switch between “single coil mode” and “humbucker mode”. You will notice that my color codes are the same as Lawrence and Gibson.
To charge up the poles, rare-earth mangets, like those used in guitar repair, are placed in the jaws of a vice. One has it’s north pole facing in and the other south. The rare-earth magnets will charge the Alnico poles with the opposite charge, north charges south and south charges north. This is because we all know that if you put two magnets with a south polarity in close proximity, they will repel or demagnetize each-other. As the bobbin with the magnets is swiped between the rare-earth magnets, it is fully charged to about 35 gauss.
Humbuckers are great for their warm, powerful tone, and best of all they “buck” the hum that single coils are usually are prone to. 60-cycle hum comes from electronics that surround us every day like florescent lights and power transformers, and it sure doesn’t sound very good when it comes through an electric guitar amp. That’s why humbuckers were such a valuable invention when music was getting louder in the 1950’s, but how do they work?
Some people don’t like how humbuckers aren’t as clear or bright as single coils, but what a lot of people don’t realize is that there are many different ways of building humbuckers to change the tone. The original Seth Lover PAF humbucker (which is the baseline against which all other humbuckers are judged) consists of 5000 uniform winds per coil (not scatterwound), bar magnets mounted underneath, adjustable poles on one side, slugs on the other, topped off with a nickel-silver cover. All of this makes for a pretty dark sounding pickup. Which might sound great in certain guitars, but some guitars beg for bright, twangy tones. You could use scatterwound coils (for a brighter, clearer sound) and solid Alnico polepieces much like a Strat pickup. This is the formula I used for my Apex Humbuckers.
Increase your tonal possibilities while leaving your Strat looking bone stock
One thing I have always loved about the Telecaster is the middle position of the pickup selector where you have the bright, aggressive tone of the bridge pickup combined with the warm, bassy sound of the neck pickup. This is a sound that you don’t normally hear coming from a Strat, but with a fairly cheap and simple mod you can achieve this and other tones, enhancing your tonal possibilities and without sacrificing any of the other tones or the looks of the guitar.
I can perform this mod to any Strat for about $50. I can also make custom, pre-made pickguards with pickups, a switch, and volume and tone controls all wired up and ready to drop in your strat. All you have to do is solder the output jack and connect it to the body with the included screws. The cost of this depends on the options you include (pots, capacitors, pickups…) the sky is the limit.
Email me at firstname.lastname@example.org to inquire about modifying your Strat.
If you are feeling particularly ambitious you can try this mod yourself. Here is a link to a wiring diagram:
Just keep in mind that you will need a good soldering iron with a small tip, a 250k push/pull pot with a short rotary knob and a second capacitor.
For many of us who love the sound of single coil pickups (eg. classic Strat or Tele) we are familiar with 60 Hz hum, radio stations, and cell phone signals coming through our amp. This is electrical interference that our single coils are especially susceptible to, and yet we refuse to give up single coils, we just love the tone too much! Humbuckers are a great way to fight this 60 Hz hum, if you have ever played a guitar with a humbucker and a true single coil you can easily hear the difference, but a lot of players complain that too much tone is lost when the hum is “bucked.” The truth is, you can stick with your old single coils as long as you follow a few DIY procedures that are guaranteed to reduce the noise to an absolute minimum. Even if you have humbucking pickups these steps will help reduce the overall noise of your rig.
Step 1. Shielding Paint
With the pickguard and electronics removed from the guitar, you can paint shielding paint from Stew-Mac on the inside of the control cavity and the pickup routs. Two or three coats (allowing it to dry overnight between coats) should provide enough coverage. All grounding material must come in contact somehow with the back of the potentiometer (ground). Connect a ground wire from the paint to the back of a potentiometer or paint up to a screw hole so the paint comes in contact with the copper tape on the back of the pickguard (see step 2).
Step 2. Copper Tape
This tape (also from Stew-Mac) is great for sticking to the back of pickguards and totally blocking out any interference. The tape is grounded by coming in contact with the switch and potentiometer casings.
Step. 3 Leads
Keeping all electrical connections to an absolute minimum length will reduce the chances of interference.
Also, twisting the positive and negative leads from your pickups (as seen on this Jazz Bass pickup) will help cancel interference. It is debatable whether this makes a noticeable difference in passive equipment, but it won’t hurt, some like it for aesthetics and wire manageability.
Step 4. Final details
Having a good quality, shielded instrument cable free of cracks and keeping it as short as possible will help tremendously in avoiding interference.
For more than 50 years, the Fender Telecaster has been manufactured pretty much the same way. It’s trademark sound is one of raw, gutsy tone with sharp attack and great clarity. Because of it’s simplicity and honesty, it is perhaps the best way to showcase a pair of single coil pickups. One of the drawbacks of true single coils is their hum which guitar makers have been trying to fix for decades. Since the Telecaster’s design was perfected rather early on in electric guitar history (1950) it is one of the only dual pickup guitars that did not have hum-canceling capabilities, and it still doesn’t today. Most of the time the two pickups are made reverse-wound/reverse-polarity so that when they are used in combination (the middle position of your pickup selector) they will cancel the hum. The telecaster design has been pretty much left alone because so many players love the trademark sound and especially the sound you get when the neck and bridge pickup are played together. For a lot of players that is more important than “bucking” the hum, but for you it might be more important to have a quiet setting on the guitar. Here I will show you how to cheaply and easily buck the hum on a standard Telecaster.
As we just discussed, most Tele pickups are wound the same direction and charged with the same polarity facing up, making them non-humbucking, so all you need to do is switch the leads and reverse the polarity on one pickup. You can test the polarity by holding a compass up to the top of the pickup as shown below. Opposites attract, so this pickup is charged SOUTH UP (fig. 1).
This morning I had in my shop a bridge pickup from a 1962 Fender Stratocaster. The pickup was not producing any sound when installed in the guitar and when hooked up to a mulitmeter, showed no resistance. This means that there is an open circuit somewhere between the positive and the negative lead wires. It is important to be very careful when working on this type of vintage gear in order to preserve the original tones of the guitar, so a number of steps were taken to carefully diagnose the source of the problem.
First, upon removing the cover I could see that this pickup uses Formvar wire, a common wire of the period, which gives it that coppery look. There is a thin layer of wax on the pickup meaning it was at some point wax potted.
I could see that the wire leading to the black, negative wire is leading to the center of the bobbin and the wire leading to the white, positive, wire is coming from the outside. This means that the wire was wound onto the pickup in a clockwise direction. If you point your finger at the left eyelet where the black lead wire is connected and then follow the wire on a path around the magnetized poles about 8,000 times and then end at the right eyelet you can see that this pickup was indeed wound in a clockwise direction.
When I oriented a magnetometer over the poles I could see that this pickup is South up with an average of 27 gauss. A bit too much magnetism for a bridge pickup for my taste, but in the interest of preserving originality I left the magnets alone.
Next I inspected the condition of the actual Formvar wire and I could see that there was no visible damage. My next step was to heat up the solder on the eyelets and add a little bit more solder. This connection can get dirty over the years and cause a bad connection.
Eureka!! After doing that I tested the resistance again and sure enough this pickup is reading about 5.44 thousand ohms of resistance, just right. I am done and the original tone of the pickup is preserved.
If heating up the eyelets had not worked my next step would have been to disconnect the finish and unwind a few coils to try to find a break. As a last resort I would have removed all of the old wire and solder, rewound the pickup with vintage-spec wire and waxed it.