When it comes to cosmic tone, itās critical to have functional potentiometers. Hereās how to install them correctly and keep them ship-shape afterward.
(Originally published March 27, 2020)
Over the last few years, we've discussed the construction of potentiometers and diagnosed several potential problems with these essential, yet sometimes pesky, electric guitar components. (If you missed these, check out āThe Trouble with Tribbles" and āDealing with Knobs and Pots.")
Let's now consider problems that can occur when replacing pots, and then discuss ways to either avoid or solve these potential issues. Over the years I've analyzed virtual cries for help from hundreds of customers, and as a result I can safely say that non-working pots fall into one of two categories that account for essentially 100 percent of the problems: (1) mechanical damage while installing the pots, or (2) soldering damage when wiring them up. It's very, very rare that a pot comes DOA from the factory. Reputable manufactures have quality control systems to prevent this, so it's almost guaranteed that a problem with a potentiometer has to do with the end user. So let's take a look at these two scenarios.
Mechanical damage.
In this case, the most common damage is caused by overtightening the nuts, especially when installing pots into a guitar with a stiff wooden top like a Les Paul.When installing pots, forget the adage "the more, the merrier." Instead, keep this in mind: The next level beyond "tight" and "super-tight" is "broken." Guitar pots don't have to handle a lot of weight or withstand a nuclear strike, so they should only be screwed down tight enough to remain immobile when you rotate the knobs.
First and foremost, it's essential that you install the pots correctly. This might sound obvious or trivial, but you can't imagine how many guitars I've seen where pots have been installed in, shall we say, unusually creative ways.
Here's how to do it right: The first step is to slip the lock washer onto the pot shaft and then insert the shaft through the hole in your guitar's pickguard or top. With the shaft protruding through the other side, now put the flash washer on the shaft, followed by the hex nut, which you can initially thread with your fingers. Finally, use a socket wrench, small adjustable wrench, or an ESP Multi Spanner to carefully tighten the hex nut until it's snug against the washer and doesn't turn anymore.
If you discover that the pot sits too high on your pickguard or guitar top, you'll need to remove the pot and start over by first threading another hex nut on the shaft, followed by the lock washer, and then repeating the installation process. This "underside" hex nut will let you adjust the height of the pot to your individual wishes. Simply insert the shaft through the pickguard or top, eyeball the height, and adjust the hidden hex nut up or down on the pot threads as needed. Finally, add the flash washer and exterior hex nut to complete the process. The key here is to always remember the correct order of these parts.
So what happens to a pot when you overtighten it? If the four tiny tabs that hold the little metal plate to the shaft, wiper, etc., are unable to withstand the force applied to the shaft when you torque down the hex nut, they'll bend and let the plate and the shaft rotate freely. Hmm, no good.
But don't worry, it's an easy fix: Use needle-nose pliers or a small flathead screwdriver to gently pull the tabs up a little more so you can rotate the plate and return it to its centered position. Then bend the tabs back into place so they hold the shaft securely (Photo 1). Done!
It's almost guaranteed that a problem with a potentiometer has to do with the end user.
Other mechanical damage is typically caused by trying to remove or install knobs that aren't made for a given pot's shaft. When you try to hammer down a non-fitting knob, you can easily break the shaft by forcing it through the knob bushing. (In most cases, this happens when trying to force a metric knob, measured in millimeters, onto a U.S. pot shaft, measured in fractions of an inch.)
If you try to remove a jammed knob that someone managed to "fit" using brute forceāor even attach with superglueāchances are good you'll break the wiper inside the pot and pull out the entire shaft along with the knob.
Yet this is easy to avoid: Never try to force a knob onto the pot shaft; instead use one that fits. If you need to remove an improperly fitted knob, use a heat gun to soften the plastic or a saw to split it open. Don't use any upward or downward pressureāthat will ruin the pot, for sure.
Soldering damage.
The easiest way to damage a pot is to overheat it, especially when attaching a ground wire to the back casing. It's a common mistake. When it comes to how long your soldering iron should be in contact with the pot, the golden rule is "as short as possible, but as long as necessary." It takes time to develop this skill, so you'll need to practice. Also, to avoid disaster it's crucial to have the right tools. Here are some helpful guidelines for soldering onto pots.
1. If you don't have a soldering station with an adjustable temperature control, you need at least two different handheld soldering irons: one rated at around 30 watts and the other around 60 watts. This is exactly what I use for any soldering job outside the shop. The 30-watt iron is for soldering on the pot terminals, pickup selector switch terminals, output jack terminalsāthose common tasks. The 30-watt iron is our daily go-to tool for all things guitar at the shop.
The 60-watt iron is for soldering to pot casings and Stratocaster tremolo claws. Don't try to solder to a pot's case with a 30-watt ironāthe solder will need a very long time to flow and you'll expose the pot to a lot of heat. With a 60-watt iron, the solder will flow instantly and soldering time will be very short. This yields strong solder joints.
2. If you want to be on the safe side, remove the case from the pot before you solder to it. That's what I do when I want to avoid damaging vintage pots. To remove the case, gently bend the four metal tabs away from you. To reinstall the case, simply bend the tabs back into place. Take your time and go easy.
3. Always rub the metal casing with 180-grit sandpaper before soldering to it. Manufacturers use all kinds of greasy coatings to protect the case against oxidation, which can make a soldering job close to impossible. So sand the case until it's clean and shiny, and then clean it with naphtha. This will provide the perfect base for a good soldering joint. But don't do this to vintage pots! For those, it's paramount to preserve the patina that comes with age.
4. If you decide not to remove the pot's case, strive to avoid any unnecessary heat. Here are some helpful tips:
- Always turn the pot down to 0 before soldering to its case.
- Use a heat sink on the case. For this job, you'll need something bigger than just a standard clip. To enhance its effect, you can chill the heat sink in the fridge ahead of time.
- If you need to connect one of the terminals to ground, as on most volume pots, don't try to solder the terminal directly to the case by bending it back. This may look cool and vintage, but you'll need a lot of heat and good soldering technique to pull this off. Simply use a piece of solid-core wire and solder it to the terminal and from there to the caseāthis yields the same performance.
- After tinning the case, let it completely cool down before you solder the wire to it.
5. Don't apply excessive solder to a terminalāit will flow down the terminal's leg and find its way inside the pot.
Photo 2 ā Photo courtesy singlecoil.com
Photo 2 shows a pot from my "Hall of Shame" collection. Look at the two red marks at the end of the two terminals. These solder blobs are what happen when you apply way too much solder. There's also a big solder blob on the middle terminal's inner ring. How someone managed to get the solder inside there will forever remain a mystery. On the upper left, notice how the carbon is melted and buckled from too much heat. This poor little thing had to endure cruel treatment ... may it rest in peace!
Remember, if you don't solder regularly, there's no shame in having a professional guitar tech do the work for youāespecially when you have a vintage guitar and need to work on its original pots. Retaining your guitar's value is an excellent investment. Soldering on pots isn't rocket science, but it requires the right tools, experience, and a steady hand.
Maintaining pots.
These are mechanical devices with a limited lifespan, and it's inevitable they'll start to wear out over time. Yes, it's possible to clean, repair, and renew the carbon inside, but this only makes sense for a vintage pot, not a modern one. Instead of trying to repair the latter, it's more cost-effective to simply replace it.
Typical pots are not completely sealed; they have open areas around the terminals, so moisture and dust can creep inside. To prevent this, you can buy pots that are completely sealed or cover standard pots with an additional dust seal. Usually a guitar's electronic compartment is closed and not directly exposed to contamination, so an additional dust cover isn't necessary for our applications.
Also, there's no need to maintain your pots. At a certain point, they'll begin to wear out and make scratchy noises when you turn them. This means it's replacement time! You can delay this a bit with contact cleaner, but this treatment is only temporary. Contact cleaner is cool for some applications, such as servicing hi-fi equipment, but it can't repair worn-out pots.
My advice? Never use contact cleaner on your pots because the cleaner will attract debris, and when it evaporates you're left with hard, dry crudāsomething you definitely do not want inside your pot. To combat this, you'll spray more cleaner and thus begin a destructive cycle. This results in replacing the pot much earlier than necessary, exactly the opposite of what you want. We all know the road to hell is paved with good intentions. If a pot is really dusty and making scratchy noisesāmaybe you took your Tele to Burning Manāthe best thing to do is open it up and swab everything with Q-Tips soaked in naphtha.
Finally, when it comes time to replace a pot, pay attention to the specs. Some pots are designed for 2,000 rotations while others are tested to withstand 20,000. You get what you pay for, and this isn't a place to cut corners.
All right! Next month we'll examine the Peavey Omniac JD, Jerry Donahue's signature model T-style, and I'll show you how to transfer its sophisticated wiring scheme to your own guitar. Until then ... keep on modding!
- Three Must-Try Guitar Wiring Mods - Premier Guitar āŗ
- Mod Garage: Three Ways to Wire a Tone Pot - Premier Guitar āŗ
- Mod Garage: Dealing with Knobs and Pots - Premier Guitar āŗ
An amp-in-the-box pedal designed to deliver tones reminiscent of 1950s Fender Tweed amps.
Designed as an all-in-one DI amp-in-a-box solution, the ZAMP eliminates the need to lug around a traditional amplifier. Youāll get the sounds of rock legends ā everything from sweet cleans to exploding overdrive ā for the same cost as a set of tubes.
The ZAMPās versatility makes it an ideal tool for a variety of usesā¦
- As your main amp: Plug directly into a PA or DAW for full-bodied sound with Jensen speaker emulation.
- In front of your existing amp: Use it as an overdrive/distortion pedal to impart tweed grit and grind.
- Straight into your recording setup: Achieve studio-quality sound with easeāno need to mic an amp.
- 12dB clean boost: Enhance your tone with a powerful clean boost.
- Versatile instrument compatibility: Works beautifully with harmonica, violin, mandolin, keyboards, and even vocals.
- Tube preamp for recording: Use it as an insert or on your bus for added warmth.
- Clean DI box functionality: Can be used as a reliable direct input box for live or recording applications.
See the ZAMP demo video here: https://www.youtube.com/watch?v=xJp0jE6zzS8
Key ZAMP features include:
- True analog circuitry: Faithfully emulates two 12AX7 preamp tubes, one 12AX7 driver tube, and two 6V6 output tubes.
- Simple gain and output controls make it easy to dial in the perfect tone.
- At home, on stage, or in the studio, the ZAMP delivers cranked tube amp tones at any volume.
- No need to mic your cab: Just plug in and play into a PA or your DAW.
- Operates on a standard external 9-volt power supply or up to 40 hours with a single 9-volt battery.
The ZAMP pedal is available for a street price of $199 USD and can be purchased at zashabuti.com.
You may know the Gibson EB-6, but what you may not know is that its first iteration looked nothing like its latest.
When many guitarists first encounter Gibsonās EB-6, a rare, vintage 6-string bass, they assume it must be a response to the Fender Bass VI. And manyEB-6 basses sport an SG-style body shape, so they do look exceedingly modern. (Itās easy to imagine a stoner-rock or doom-metal band keeping one amid an arsenal of Dunables and EGCs.) But the earliest EB-6 basses didnāt look anything like SGs, and they arrived a full year before the more famous Fender.
The Gibson EB-6 was announced in 1959 and came into the world in 1960, not with a dual-horn body but with that of an elegant ES-335. They looked stately, with a thin, semi-hollow body, f-holes, and a sunburst finish. Our pick for this Vintage Vault column is one such first-year model, in about as original condition as youāre able to find today. āWhy?ā you may be asking. Well, read on....
When the EB-6 was introduced, the Bass VI was still a glimmer in Leo Fenderās eye. The real competition were the Danelectro 6-string basses that seemed to have popped up out of nowhere and were suddenly being used on lots of hit records by the likes of Elvis, Patsy Cline, and other household names. Danos like the UB-2 (introduced in ā56), the Longhorn 4623 (ā58), and the Shorthorn 3612 (ā58) were the earliest attempts any company made at a 6-string bass in this style: not quite a standard electric bass, not quite a guitar, nor, for that matter, quite like a baritone guitar.
The only change this vintage EB-6 features is a replacement set of Kluson tuners.
Photo by Ken Lapworth
Gibson, Fender, and others during this era would in fact call these basses ābaritone guitars,ā to add to our confusion today. But these vintage ābaritonesā were all tuned one octave below a standard guitar, with scale lengths around 30", while most modern baritones are tuned B-to-B or A-to-A and have scale lengths between 26" and 30".)
At the time, those Danelectros were instrumental to what was called the ātic-tacā bass sound of Nashville records produced by Chet Atkins, or the āclick-bassā tones made out west by producer Lee Hazlewood. Gibson wanted something for this market, and the EB-6 was born.
āWhen the EB-6 was introduced, the Bass VI was still a glimmer in Leo Fenderās eye.ā
The 30.5" scale 1960 EB-6 has a single humbucking pickup, a volume knob, a tone knob, and a small, push-button āTone Selector Switchā that engages a treble circuit for an instant tic-tac sound. (Without engaging that switch, you get a bass-heavy tone so deep that cowboy chords will sound like a muddy mess.)
The EB-6, for better or for worse, did not unseat the Danelectros, and a November 1959 price list from Gibson hints at why: The EB-6 retailed for $340, compared to Dano price tags that ranged from $85 to $150. Only a few dozen EB-6 basses were shipped in 1960, and only 67 total are known to have been built before Gibson changed the shape to the SG style in 1962.
Most players who come across an EB-6 today think it was a response to the Fender Bass VI, but the former actually beat the latter to the market by a full year.
Photo by Ken Lapworth
Itās sad that so few were built. Sure, it was a high-end model made to achieve the novelty tic-tac sound of cheaper instruments, but in its full-voiced glory, the EB-6 has a huge potential of tones. It would sound great in our contemporary guitar era where more players are exploring baritone ranges, and where so many people got back into the Bass VI after seeing the Beatles play one in the 2021 documentary, Get Back.
Itās sadder, still, how many original-era EB-6s have been parted out in the decades since. Remember earlier when I wrote that our Vintage Vaultpick was about as original as you could find? Thatās because the modelās single humbucker is a PAF, its Kluson tuners are double-line, and its knobs are identical to those on Les Paul āBursts. So as people repaired broken āBursts, converted other LPs to āBursts, or otherwise sought to give other Gibsons a āGolden Eraā sound and look ... they often stripped these forgotten EB-6 basses for parts.
This original EB-6 is up for sale now from Reverb seller Emerald City Guitars for a $16,950 asking price at the time of writing. The only thing that isnāt original about it is a replacement set of Kluson tuners, not because its originals were stolen but just to help preserve them. (They will be included in the case.)
With so few surviving 335-style EB-6 basses, Reverb doesnāt have a ton of sales data to compare prices to. Ten years ago, a lucky buyer found a nearly original 1960 EB-6 for about $7,000. But Emerald Cityās $16,950 asking price is closer to more recent examples and asking prices.
Sources: Prices on Gibson Instruments, November 1, 1959, Tony Baconās āDanelectroās UB-2 and the Early Days of 6-String Bassesā Reverb News article, Gruhnās Guide to Vintage Guitars, Tom Wheelerās American Guitars: An Illustrated History, Reverb listings and Price Guide sales data.
Some of us love drum machines and synths, and others donāt, but we all love Billy.
Billy Gibbons is an undisputable guitar force whose feel, tone, and all-around vibe make him the highest level of hero. But thatās not to say he hasnāt made some odd choices in his career, like when ZZ Top re-recorded parts of their classic albums for CD release. And fans will argue which era of the bandās career is best. Some of us love drum machines and synths and others donāt, but we all love Billy.
This episode is sponsored by Magnatone
An '80s-era cult favorite is back.
Originally released in the 1980s, the Victory has long been a cult favorite among guitarists for its distinctive double cutaway design and excellent upper-fret access. These new models feature flexible electronics, enhanced body contours, improved weight and balance, and an Explorer headstock shape.
A Cult Classic Made Modern
The new Victory features refined body contours, improved weight and balance, and an updated headstock shape based on the popular Gibson Explorer.
Effortless Playing
With a fast-playing SlimTaper neck profile and ebony fretboard with a compound radius, the Victory delivers low action without fret buzz everywhere on the fretboard.
Flexible Electronics
The two 80s Tribute humbucker pickups are wired to push/pull master volume and tone controls for coil splitting and inner/outer coil selection when the coils are split.
For more information, please visit gibson.com.