An Introduction Into The World Of Replacement Pickups (Part 2)

Jan14

Review

In the first article of this two-part series (The Definition of Tone), we took an introductory look at the world of replacement pickups for electric guitars. As much a part of a guitarist’s signature sound as wood or fingers, pedals or amplifiers, the pickups are the starting point where the guitar’s sound becomes electric. While it can be tricky to find the pickups that will help you find ‘your voice’, there is really no excuse for crummy tone these days. Guitarists on a quest for satisfying sound have a very wide variety of high-quality aftermarket pickups from which to choose.

As you might recall, I was in search of replacement pickups for my late 80’s Ibanez 540s. This guitar has a lightning fast neck, a very attractive cherry sunburst, tiger-striped maple top, and major mojo. With the right pickups, I knew this would be my “number 1″ guitar. It has double coil (humbucker) pickups in the neck position and bridge position and a single coil pickup in the middle position (known as an H-S-H configuration).

From the neck pickup, I wanted to be able to get warm, clean tones for both rhythm playing and single-line solos in a jazz setting. I also wanted to be able to get a smooth, singing sustain when using the neck pickup for high-gain soloing reminiscent of the sounds that Carlos Santana gets. If possible, I’d want to be able to get some “Strat-like” funk and grit from this pickup when I split one of the coils and used a crunchy, mid-gain setting.

From the bridge pickup, I wanted a great ‘power-chord’ sound that was neither too muddy nor too thin, and a harmonic-rich lead tone that really cuts through for rock solos without sounding shrill on the high notes.

From the middle pickup, I hoped to be able to produce a very interesting sound for clean rhythm guitar parts, mostly balanced across the frequencies with perhaps slightly de-emphasized bass response and treble with a hint of that “chime-y or glassy” quality. I also wanted the ability to combine the middle pickup with the neck or bridge pickups in order to get those interesting “position 2 and 4″ sounds that a Strat can get (sometimes referred to as ‘quack’), especially with a clean amp setting. I also wanted try to get rid of the annoying 60 Hz hum that single coil pickups cannot eliminate.

Final Selection

I listened to a lot of sound-clips and asked a lot of questions of guitar players familiar with different pickups. I considered pickups with ceramic magnets, alnico 2 magnets, and alnico 5 magnets. I considered pickups with regular pole pieces, small allen-screw pole pieces, oversized pole pieces, staggered-height pole pieces, and ‘blade type’ pickups without individual pole pieces at all. For purposes of blending the humbuckers nicely, I decided to select pickups of the same magnet type for the neck and the bridge. It turns out that alnico 5 magnets were used in the highly coveted vintage humbuckers from the late 1950’s, so I focused my search to pickups in the PAF family. (PAF stands for patent applied for and refers to the pickups used on Gibson guitars back in the 50’s. These pickups had the letters PAF stamped on them and the nickname stuck.) I chose the “59” pickup from Seymour Duncan for the neck position. I decided to get the “4-wire” option to allow me the coil splitting configurations I was hoping for. Wanting a slightly more modern sounding pickup, I selected the “Custom 5″ model for the bridge position. Finally, I decided on the “Duckbucker” from Seymour Duncan for the middle position. This pickup is designed to produce the desired ‘quack’ sound but in a stacked double coil configuration that provides the 60-cycle hum-canceling effect and still fits in a single coil-sized hole. I was comforted to know that Seymour Duncan pickups come with a 21-day trial period. If for some reason the pickups weren’t satisfying in my guitar, I could send them back and try some another model until I was happy with the results.

Circuit design

Even before I had made my final pickup selections, I knew that my wiring diagram would be fairly intricate in order to get the pickup combinations I desired. I’d want not only to be able to have each of the humbuckers operate with both coils on, but also to be able to split either of the coils for single coil sounds. This was not a common wiring approach as most coil-split circuits provide for only one of the coils to be split. I wanted to be able to combine the neck and bridge pickups in parallel – not only as dual humbuckers, but also as the top coil of the neck pickup combined with the bottom coil of the bridge pickup, and vice versa. These “outer” and “inner” coil combinations became very popular in the mid 80’s when Paul Reed Smith guitars introduced the 5-position rotary switch for their dual-humbucker guitars. These combinations can produce some interesting ‘scooped’ sounds reminiscent of Strat or Tele tones. My “wish list” represented 9 combinations so far, and I hadn’t even considered the middle pickup (alone and in combination) yet! I knew my stock hardware wasn’t going to get me what I hoped for.

In addition to a “five position, two pole” pickup selector switch, the guitar had one master volume control potentiometer (or “pot”) and one master tone control pot. It also had a double pole-double throw (DPDT) “on-off” mini toggle switch to allow splitting of one coil from the humbuckers. In order get the desired “upper coil / both coils / lower coil” combinations from the humbuckers, I knew this mini toggle would have to be replaced by a DPDT “on-off-on” mini-toggle switch. I developed a circuit diagram that allowed me to pick the upper coil from the neck pickup at the same time that I was selecting the lower coil of the bridge pickup, and vice versa. In order to preserve the hum canceling properties of the outer and inner combinations, I would need to reverse both the magnet polarity and direction of the winding for one of the pickups. (see open pickup surgery below)

So far, I had realized my goals for positions 1 and 5 of the 5-way switch, and felt confident that I could get what I wanted in positions 2 and 4. It was position 3 that I was stuck on. I wanted to be able to use position 3 for the middle pickup by itself, but I also wanted to be able to use position 3 to combine the humbuckers. I needed another switch, but didn’t want to drill another hole into the guitar. I decided to use a “push/pull” DPDT switch built into the pot that I would use as the volume control. While I was changing out this pot for one that includes a DPDT switch, I decided to use an audio taper pot instead of the linear taper pot that was in the guitar. The audio taper pot provides a smoother range of control as the pot is rolled from the lowest value to the highest, conforming more closely to the way the human ear perceives changes in volume. (note: Humbuckers typically need 500K ohm pots for best results.)

The stock pickup selector switch did not provide a straightforward way for combining the humbuckers, so I researched options and found a 4-pole, 5-way switch known as the “superswitch”. I designed a circuit to get exactly what I wanted, but was set back when I discovered that the superswitch was too deep in its physical dimension to fit inside the shallow control cavity of my guitar. So, forced to reuse my stock 2-pole, 5-way selector switch, I cobbled together a ‘work around’ that was functional, but inelegant in implementing all the choices I wanted. In position 3, when the push / pull switch was ‘pushed’, I would have the middle pickup by itself. When the push / pull switch was ‘pulled’, I would have the combination of the neck and bridge pickups as dictated by the on-off-on mini toggle (i.e. outer coils parallel / neck and bridge double coils parallel / inner coils parallel).

Open pickup surgery

In order to preserve hum-canceling when combining the inner or outer coils of the neck and bridge pickups, I had to reverse the magnetic polarity and winding direction for one of the pickups. I decided (arbitrarily) to make the change on the neck pickup. By gently loosening the screws in the base plate, I was able to separate the pickup bobbins from the housing. I then unwound the cloth tape that protected the pickup windings. This revealed the magnet nestled on the underside of the pickup between the pole pieces. I carefully slid the magnet out, flipped it over like a pancake, and slid it back into place. After re-taping the bobbins, I tightened up the screws on the base plate, and I was done. Total elapsed time, about 3 minutes. In order to reverse the direction of the winding, I simply treated the ‘start’ end of the winding (in the case of Seymour Duncan humbuckers, the black wire) as the finish and the ‘finish’ end (green) as the ‘start’. This change would be invisible when running the pickup by itself, but would make all the difference in preserving hum cancellation when one coil from the neck pickup was paired with one coil from the bridge pickup.

Installation

Installation went very smoothly. I used a ‘star ground’ technique to avoid any ground loops. This technique joins all the parts of the circuit that need to be grounded at a single point as the rays of a star emanating from the center. The ground wires from the pickups and the pots and the chassis were all grounded to the audio return on the guitar output jack. I used 22 gauge solid core copper wire, but wished I had some stranded wire on hand as it is typically easier to work with and is less prone to breaking. I tinned all the leads prior to soldering and was careful to heat the joint, not the solder. This is important in order to prevent ‘cold’ solder joints that can cause unreliable connections during operation. I had left one of the strings on the guitar in order to have an easy way of testing the guitar before buttoning up the back plate. I also tapped on the pole pieces with a tiny screwdriver (keep the volume down!) in order to make sure that the switches were providing the correct combinations. When the guitar checked out 100% it was time to string it up and take it for a test drive. Total installation time was approximately 90 minutes.

Final Results

I couldn’t wait to plug the guitar into my rig to test it out and hear the results. First I made sure that the pots were working (check!). I dialed in a clean setting and strummed a jazzy chord using the ’59 neck pickup set as a humbucker. I was delighted to hear such a full tone, a bit darker than I could ever coax from the original pickup, with a very rich midrange. Even with arpeggiated licks high on the neck, the tone was never brittle, even with the tone control maxed out. I then dialed in a high gain setting and the guitar gave forth a sustain like it never had before. It had a slight hint of natural compression without any artificial quality at all. Fast licks had a good balance between rounded slur and crisp articulation. I knew that this pickup was demonstrably better than the pickup it had replaced, but I hadn’t even begun to really reveal its versatility. I then flicked the mini toggle to split the upper coil. Back to a clean amp setting, I played a handful of blues licks with bends and double stops. No one would ever confuse it for a vintage Strat, but it was most assuredly a single coil tone with a pronounced ‘snap’. The tone darkened up a by a subtle amount when I split to the lower coil instead. Again, decidedly single coil, but no one would be forgetting Stevie Ray Vaughn’s or Eric Johnson’s tone any time soon. I decided to see if I could find out what this pickup was NOT good at and it didn’t take long. To my ears, it was entirely too muddy for hard rock power chords. I didn’t consider this a shortcoming because I never intended to use it in such an application. I suppose a punk rocker that wanted to create a thick wall of noise would find it quite useful.

I switched down to the Custom 5 pickup and did the same kinds of tests from the bridge position. With a crunchy hard rock rhythm setting on the amp, I got a very hot ‘power chord tone’. Thick with solid low end and nuanced mid ranges, it was decidedly ‘scooped’, especially compared to the Seymour Duncan JB pickup I have in the bridge position of another guitar. Instantly, I knew that this was a major step-up from the original pickup. Stepping up the gain and playing my best imitation of flashy hard rock solos, this pickup did not let me down. It had a nice high end that wasn’t shrill at all and didn’t get muddy when playing some low notes on the wound A and E strings. I needed to tweak the pickup height down a bit in order to get a good clean sound, which thankfully didn’t alter the ‘hot’ sounds noticeably. Splitting the coils had much the same effect as was evident when splitting the neck coils. The lower coil was a bit brighter than the upper coil, and while both were musically useful, neither was a stand out. (Like the man said, “if you want to sound like a Strat, buy one!”). I found that the single coils ‘crunched’ passably, but in high gain settings, they simply weren’t my cup of tea. Again, this was never my objective, so I wasn’t terribly disappointed.

As if the results thus far were a mere opening act, I switched to the middle pickup not knowing what to expect. The first thing that struck me was how quiet the Duckbucker was. Intellectually, I knew it should be quiet owing to its humbucker construction. I just didn’t consider the psycho-acoustic impact of switching to position 3 and hearing absolutely no noise. Dialing in a clean setting I started a few licks of my poor impersonation of a ‘chicken picker’. I was stunned! The snap and twang that I had hoped for was in full effect! Very bright and punchy, this pickup revealed ‘inner’ nuances to my favorite jazzy chords that I had never heard. It had a lovely chime to it with a “shimmery” high-end sustain. I started playing some bluesy licks and noticed a problem instantly. As I bent the strings, the volume would drop off very noticeably, and then increase as I released the bend. I suspected that the very narrow pole pieces were too far from the strings. I raised the pickup as close to the strings as I could without hitting it with my pick. The ‘volume drop’ problem was essentially gone, but it seemed to lose a bit of it’s ‘shimmer’ and ‘snap’. Pickups that are too close to the strings can rob a guitar of sustain as the pull of the pickup’s magnet physically dampens the string’s vibrations. Some tweaking will be needed to find the lowest possible height that I can get away with without seeing the ‘volume drop’ problem return. Another possible remedy would be to try the Seymour Duncan Vintage Rails pickup because it has tonal characteristics essentially identical to the Duckbucker, but with a blade design instead of individual pole pieces.

I then combined the Duckbucker with the neck pickup in all three mini-toggle positions. I was surprised to hear the nice varieties of tones that I could get. One of them was sure to work as a reasonable approximation of the Sultans of Swing sound, and another worked nicely for the Comfortably Numb / Brick In The Wall tone. Combining the Duckbucker with the bridge had similar results, only a bit brighter than the Duck/neck combos. In a critical listening environment, a schooled ear would readily know that this was not a Strat in positions 2 and 4. But in a live band situation, the sound would be plenty sufficient to evoke the familiar tones.

When I returned the 5-way switch to slot 3 and pulled up on the push/pull pot, I was treated to tones that this guitar had never produced. The dual parallel humbucker tone was dead-on for an old Gibson LP in the middle position. It rang out with full humbucker presence, but with a little extra top-end crispness and little extra low-end tightness. Adding a slight hint of crunch, I was able to get tones reminiscent of Steely Dan guitar tones from the 70’s. Very, Very cool ! Toggling up to get the ‘outer’ coil combo was exactly what I had hoped for. A very desirable tone approximating a “spanked” Tele was immediately present. (think Keith Richards crunchy rhythm sound) The ‘inner coils’ gave a slightly altered tone that had it’s peak shifted a bit to the midrange. Equally appealing, equally musical. Neither of these combinations had a trace of hum (the surgery was a success!). These last combinations rounded out the test drive that took me through all 16 unique combinations from this guitar.

Aside from the personal satisfaction from accomplishing my objectives in this do-it-yourself project, I got a HUGE smile on my face the first time I took this guitar out for a gig. Our soundman (a fellow guitarist who owns many expensive guitars, amps, and other toys) was floored by how good my tone was with just my guitar, a cord, a small Fender solid state combo amp and a touch of reverb. The notes seemed to jump off the fingerboard with a new crispness and the hi-gain solo tone was just transcendent. I played the best I ever had with this band that afternoon, even taking a few extra choruses on Cause We’ve Ended as Lovers (check out Jeff Beck’s Blow by Blow CD for the definitive version of this Stevie Wonder composition). This guitar is officially ‘number one’ for me.

Conclusion

My total cash outlay for this project was under $250 and total time spent was approximately three hours (not counting research).

Inspiring tone can really stimulate a player to new heights of creativity, and noodling with the pickups is a fun and effective way to get very close to the heart of the tone. I hope this two-part series was informative and inspiring to readers who have considered getting “under the hood” and tricking out their axes to get a custom “hot-rod” sound. Gentlemen (and ladies), Start your soldering irons !!

I am grateful to all who helped me with my journey, especially my ‘tone brothers’ on the Seymour Duncan website message forum. Special thanks also to John at BlackroseCustom.com and Lew at lewsguitars.com for excellent advice and fast service.

Also check out… Replacement Pickups Part 1

About Bill Cozzo

Philadelphia-area native Bill Cozzo has been playing guitar for over 20 years, starting in high school by teaching himself Beatles tunes on an old acoustic guitar. After taking time off to focus on career and start a family, Bill returned to playing in 2001 when he met up with the folks from Frantic Moon (a dance-rock cover band) and Creative Doubt (an eclectic, "improv-friendly" rock cover band).

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