Photo 1
Here's a case in point: Recently a client brought me his 1993 Strat (Photo 1) for a setup. His primary concern was that he was having a problem staying in tune, especially when bending one string while holding another. While we were discussing this, he revealed he rarely used the tremolo and kept the bar swung back out of the way when he played. Based on this, I recommended he allow me to lock his tremolo down—or "deck" it against the body. I knew this would resolve many of the tuning issues he was having. He agreed and I proceeded with the relatively simple project described below.
If you're a Strat player who doesn't find much utility in the trem system, you might consider doing this too. This tweak isn't for everyone—many Strat players feel the trem provides much of the guitar's magic. But there are also those who play a Strat because they love its pickups, scale length, weight, and feel, but prefer the stability of having its bridge locked down tight against the body. Some even swear this increases sustain.
Fortunately, it's a reversible mod, so you can try it out and see for yourself. If the tuning advantages outweigh losing whammy capability, great. If you find you miss your trem, you can always return to a floating bridge setup. (I explain that process in the DIY video "How to Float a Strat Trem.")
Evaluating the guitar.
Photo 2
This Strat had spent some time on the road, but it was in good shape. It had a vintage-style, six-screw bridge—not the two-post design of modern Strats. I noticed there were only two springs holding the tremolo to the claw, which explained why the bridge was tilting forward so much (Photo 2).
It's crucial to know the intended tuning and string gauges before you set up a Strat. My client explained he strings up with .010-.046 sets and tunes to standard pitch (unlike some Strat players who tune down a half-step à la Hendrix and Stevie Ray Vaughan).
Getting started.
Photo 3
Getting started. The first step is to remove the cover plate on the back so you can access the claw and trem springs. To provide maximum stability, I added three more springs to the claw (Photo 3) and then used a Phillips screwdriver to move the claw toward the body and tighten the five springs (Photo 4).
Photo 4
The goal is to tighten the springs enough so the tremolo doesn't move when you bend a string. At this point, we're just roughing in the spring tension—we'll come back and fine-tune it in a moment.
Tip: Remember to tune the guitar after every adjustment. If you neglect to do this, you may have to redo your work. This holds true for every step of a setup, including adjusting a truss rod, setting saddle height, and intonating the strings.
Take it to the bridge!
Photo 5
Next, turn the guitar over and make sure the six mounting screws holding the tremolo to the body are all adjusted flush to the bridge plate (Photo 5). Don't tighten them too much, otherwise the tremolo will rock forward on its beveled edge. Lower each screw just enough for the bridge plate to sit flat and flush with the body.
Testing one, two.
Tune up and test the spring tension by bending the strings. Does the trem move at all? If so, tighten the claw a bit closer to the body. Hold a note on one string and bend another against it. You want the held note to stay in tune as you bend the other string. Keep in mind that some guitar necks flex a bit when you bend a string and this will subtly affect the tuning. In this case, we're only paying attention to the tremolo to see if it rocks forward when bending strings.
Be patient: You may need to tighten the springs several times before the trem stays rock solid when you bend. Remember to always tune after every adjustment. Once the trem is secured flush to the body and doesn't tilt forward when you bend strings, it's time to move to the final setup stage.
Adjust the saddles.
Photo 6
Now adjust the action at the bridge saddles. Using an Allen wrench, adjust the two screws to position each saddle to your preferred height (Photo 6). Make sure each saddle stays level and doesn't tilt, and adjust the saddles in a gentle arc that matches the fretboard radius. I explain this operation in "How to Set Up a Fender Stratocaster."
Final setup.
After decking the trem and adjusting the action, the strings may be sitting too close to the pickups and this can negatively affect intonation. So we have to check the pickup height before doing anything else. If you want to brush up on this, read "How to Balance Pickups on Strats and Teles."
After adjusting the pickups, then tackle the intonation. Again, I detail this process in "How to Set Up a Fender Stratocaster."
Beware of Stripped Screw Holes
Occasionally when locking down a Strat trem I've encountered worn out screw holes, either at the spring claw or bridge plate. Stripped-out holes must be doweled and re-drilled, otherwise the screws will continue to strip out more wood and will eventually slip out of the hole. Last year I wrote a column about fixing stripped-out holes for pickguard screws, and the same principles apply here, although in this case the holes are bigger and require a slightly larger dowel. Check out "Got a Loose Screw?" for complete details. Remember, if you don't have the proper tools or knowledge to correctly do this—or any guitar job—play it safe and consult your local guitar tech.
Tip: Always put fresh strings on your guitar before you adjust the intonation.
All right—that's it! You've now locked down your trem and should have a much easier time keeping your guitar in tune.
[Updated 9/24/21]
• Testing pickups (impedance and functionality).
• Mapping out a switch.
• Testing a guitar cable.
• Identifying the lugs on a TRS output jack.
• Checking battery life.
Testing pickups. On many occasions I’ve used a multimeter before buying a used pickup. I learned the importance of this the hard way when I bought a used pickup at a guitar show, only to discover it didn’t work when I got it home. If I’d brought a multimeter with me, I could have tested the pickup on the spot and saved some money.
It’s a simple process to test a pickup. Set the multimeter to the ohm setting and touch its red test lead to the pickup’s primary lead (hot) and touch the black test lead to the pickup’s ground wire.
Photo 2
If you’re testing a humbucker with four conductors, make sure that the wires are properly attached to each other. For example, before you try to measure the impedance on a Seymour Duncan humbucker (Photo 2), make sure that the red and white leads are connected to each other and isolated from any other connection, and the green and bare leads are also connected to each other. Touch the red test lead from the multimeter to the black wire—the pickup’s primary lead. Touch the multimeter’s black test lead to the green and bare ground wires on the pickup. This should give you an accurate impedance measurement.
To make sense of a particular model pickup’s reading, check with the manufacturer for its exact impedance. If the impedance measurement you take is significantly lower than the manufacturer’s rating, then you know there’s something wrong with the pickup.
only to find you have no signal?
A multimeter can tell you a lot about a pickup before you wire it up. For example, humbuckers typically measure at around 8k ohms for a vintage-style pickup to as much as 25k for a high-output pickup. The 16.25k reading we see in Photo 2 indicates this is a hot humbucker. Single-coil pickups can range from 6k (vintage) up to 16k (high-output).
Mapping out a switch. If you don’t have a diagram to follow, wiring a new switch can be frustrating. An easy way to save time when tackling a wiring project is to use your multimeter to map out the switch. Simply set your multimeter to the continuity setting, which is marked with a speaker or soundwave icon. This setting will produce an audible tone to let you know when a circuit is closed.
Photo 3
On a 3-way toggle switch, for example, touch either one of the side lugs with one of the test leads from the multimeter, then touch the middle lug—that’s typically the output—with the other test lead (Photo 3). If you hear a tone, then you know the switch is on in that position. If there’s no tone in that position, the switch is off.
Photo 4
It’s a similar process for a Strat-style 5-way blade switch (Photo 4). Touch the last lug on the switch—this will be the output lug—with one of the test leads from the multimeter. Then touch each of the other lugs with the other test lead and listen for the tone. By carefully working through each switch position, you’ll be able to locate its corresponding input lug. As you map a switch’s connections, draw a diagram so you’ll have something to refer to in the future.
Testing a guitar cable. Have you ever arrived at a gig or rehearsal only to find you have no signal? The worst part is not knowing where the problem lies. Is the amp blown? Does the guitar have a loose output jack? Chances are it’s the guitar cable—that’s the place to start troubleshooting. The good news is, it’s quick and easy to test your cable with a multimeter.
Photo 5
Set your multimeter to test continuity, then touch the tip of both cable plugs with the test leads (Photo 5). If you hear a solid tone, you have a connection. But don’t stop there: Move the cable around a little to see if it has a short, and test it again. If after shaking the cable and testing it several more times you continue to get a solid tone, you can assume the cable is good. However, if the test tone is intermittent you’ll know there’s a problem. You should also test the ground on the cable. Simply touch the shaft of both plugs with the test leads and listen for a solid tone.
Testing a TRS jack. The output jacks on passive guitars are pretty simple—they have one lug for the primary lead and one for the ground. However, output jacks for an active system have three lugs. Called a tip/ring/sleeve (TRS) jack, these are common in electric guitars with active pickups or onboard circuitry, and are found in most acoustic guitars equipped with an internal preamp. The tip is for the primary lead, the sleeve is for a battery switch that turns the battery on when a cable is plugged into it, and there’s also a ground to complete the circuit for the electronics.
Sometimes the lugs for the tip and sleeve are different lengths, which makes them easier to identify, but many TRS jacks have the same length lugs with no markings to let you know which one is for the battery and which one is for the primary lead. This can be problematic if you’re installing a new pickup system into an acoustic guitar, adding active electronics to a solidbody, or troubleshooting an existing setup. But once again, the multimeter makes it easy to sort this out.
Photo 6
First plug a guitar cable into the output jack and switch your multimeter to the continuity setting. Touch one of the test leads to the tip of the guitar cable’s exposed plug and touch the other test lead to one of the lugs on the TRS output jack (Photo 6). Listen for a tone to identify which lug makes the connection. The lug that gives you a tone while you’re touching the plug tip is where you’ll attach the primary lead from a pickup or preamp.
Next, while still touching the plug’s tip with the test lead, touch the other lug on the jack. There should be no tone. Keep your test lead on that lug and move the other test lead from the plug’s tip to its shaft. You should hear a tone. This identifies the lug you’re currently touching as the battery switch for the active electronics in your guitar.
Testing batteries. Given the amount of battery-operated gear most guitarists have in their rig, it can be a challenge to stay on top of available battery power. You don’t want to arrive at a gig with a dying battery in a stomp, but you certainly don’t want to swap out all the batteries in your gear before every show. Some may still have plenty of life in them, so why not do a battery check to get the facts? (Of course, once you reach a certain number of pedals, it makes economic and ecological sense to get a powered pedalboard and be done with batteries.)
In the early days of rock ’n’ roll, guitarists would test a 9-volt battery by touching its terminals to their tongues—not a very accurate (or sanitary) approach. If you received a mild shock, the battery was deemed gig-worthy. The best way to test a battery is with a multimeter. With it, you can test just about any type of battery: AA, 9-volt, lithium, or even a disc battery.
Photo 7
Set the multimeter to the DC V setting (and if your multimeter offers it, to the appropriate voltage range). Now touch the red test lead to the plus battery terminal and the black test lead to the minus terminal. The multimeter will display the battery’s voltage (Photo 7). If you’re testing a 9-volt battery and the display on the multimeter reads less than 9 volts, the battery is weak. If the battery measures 9 volts or more, you’re good to go.
Each guitar has its own resonant frequency. Some guitars are bright, some are darker, and some are just flat-out midrange heavy. In large part this has to do with the density of the wood and the quality of the hardware, which helps explain why certain makes and models of pickups can sound fabulous in one guitar, but not so good in another. If your humbuckers sound too dark, rewiring them could be the perfect solution. It’s certainly worth trying before you replace them.
Some background. The two coils in a humbucker are typically wired in series. This produces the highest output, but also the darkest tone. If a humbucker has a 4-conductor harness, its coils can easily be wired in parallel. In this configuration, you lose about 20 percent of your volume, but the tone is brighter and cleaner.
When a humbucker’s coils are connected in series, the signal path of the first coil flows through the second coil and then on to the pickup selector switch, volume pot, and output jack. When wired in parallel, the two coils still operate together, but the signal path doesn’t travel from one coil into the other.
Photo 2
Planning the procedure. Stock Seymour Duncan JB and Jazz humbuckers are wired in series. Before we can modify the 4-conductor harness to wire the coils in parallel, we need to understand the Duncan color codes (Photo 2). Except for the bare ground wire, each colored wire is either the “start” or “finish” of a coil. How these wires are connected determines whether the pickup is wired in series or parallel. Here’s the breakdown:
• Black is the start of coil 1.
• White is the finish of coil 1.
• Green is the start of coil 2.
• Red is the finish of coil 2.
• Bare wire is always the ground.
Note: This applies only to Duncan pickups—other manufacturers use different color-coding schemes. See “Obey Your Color Codes” for more details.
Photo 3
Photo 3 shows these five wires connected in a series configuration. We have the black wire acting as the hot or primary lead, and the red and white wires are soldered together to create the series link (that is, they connect the two coils).
Fig 1
The green wire is connected to the bare wire and then soldered to the back of a pot to create a ground. Figure 1 shows how the hot wires connect to the 3-way blade switch for series wiring, and how the switch itself is configured.
Photo 4
Photo 4 illustrates how to connect the wires of a 4-conductor Duncan humbucker in a parallel configuration. As you can see, black and red are joined—they become the hot or primary lead. White and green are connected to the bare wire to become the ground, and all three are soldered to the back of a pot. The parallel wiring diagram for the 3-way switch is show in Figure 2.
Fig 2
By wiring the humbucker in parallel, we have connected the start of coil 1 to the finish of coil 2. For the ground, we have connected the finish of coil 1 to the start of coil 2 and both are joined to the bare wire.
Doing the deed. After removing the strings and pickguard, unsolder the pickup wires from the switch and pots, being careful not to overheat them. Separate the wires from each other with your soldering iron. Next, twist and solder the black and red wires together. Do the same for the green and white wires, and join them to the bare wire. Now solder the black and red to the input lug on the 3-way switch, and the green, white, and bare wires to the back of one of the pots.
That should do it. Put the pickguard back on, restring, and test out your new tones.
Obey Your Color Codes
Different pickup manufacturers use different color codes for their 4-conductor humbuckers, so before you start brandishing that hot soldering iron, make sure you’ve got the right color codes and have figured out how to connect the wires. Here are a few parallel wiring combinations for several other popular pickup manufacturers.- DiMarzio: Red and white are hot, black and green are ground.
- Gibson: Black and white are hot, green and red are ground.
- Jackson: Green and red are hot, white and black are ground.
Plan of attack. I decided to install a CRL 3-way switch, a high-quality unit you can get from such luthier suppliers as Allparts and Stewart-MacDonald. (Oak Grigsby and Switchcraft are two other excellent brands.) Though they cost a few more bucks than cheapos, good switches will give you much longer service and are well worth the investment.
After gathering your tools and supplies (soldering iron, 60/40 solder, 12-gauge stranded wire, hemostats, and a medium-tip Phillips head screwdriver), unscrew the control plate, flip it over, and eyeball the existing 3-way switch. Remember to place the screws in a small box so you don’t lose them. Plus, you don’t want a wayward screw to end up under the guitar because it will scratch the finish.
Tip: Before you unsolder and remove the switch, draw a diagram of how it’s wired. Even if your new switch comes with a diagram, it’s a good idea to document where each wire is attached on the original one.
Fig. 1
The old switch in this guitar used the traditional Fender wiring, so my diagram looked like Fig. 1. This is the standard Tele configuration.
Fire up the iron. The next step is to unsolder the two pickup wires from the blade switch. On a stock Tele with single-coils, there should be one lead wire to remove for each pickup. When soldering or unsoldering a wire, grip it with a pair of hemostats so you won’t burn your fingers! Once the solder is molten, give the wire a gentle yank to pull it free.
In addition to the pickup leads, there’s one wire that connects the output of the switch to the input of the volume control. Unsolder this wire from the switch only. In all, there are three wires to unsolder from the switch.
Detach the old blade switch. Next remove the two mounting screws that fasten the original switch to the control plate. Typically these are Phillips head screws, but some guitars require a small flathead screwdriver. The blade switch should drop right out of the control plate.
If you have a guitar with an inexpensive “box” switch, confirm that the mounting holes line up properly for the new switch you intend to install. Some imported guitars have different hole spacing than U.S.-built models for mounting the switch onto the control plate. If that’s the case, you’ll either need to get a new box switch or swap out the old control plate for a new one with hole spacing that matches an American CRL switch.
Photo 2
Photo 2 shows the CRL switch I’m about to install. Take a moment to compare it to the wiring diagram. Use the spring to orient yourself with the various lugs and their functions.
Install the replacement switch. CRL switches come with mounting screws, and you can either use them or the screws from the original switch, assuming they fit. Mount the switch on the control plate, then insert and tighten the screws.
Note: You can install the switch oriented in either direction, but sorting out the wiring will be easier if the new switch is oriented the same way as the original. In other words, if the spring on the old switch was facing the pickups, then mount the new switch that way too.
Wire up the new switch. There are four lugs for attaching wires on each side of the blade switch, making a total of eight lugs. For this classic Tele scheme, we only need to solder three wires onto six lugs. Each pickup lead will have its own dedicated lug. The other four lugs will be used to join both sides of the switch and connect the switch to the volume pot.
Before you begin wiring, review this simple breakdown of the switch while comparing it to the diagram. Each number represents a different lug on the switch. Next to the lug number is a description of the wire you’ll need to solder.
Spring side of the switch
1. Output wire to volume pot
2. Connects to prong #1 (switch output)
3. Unused
4. Lead from neck pickup
Non-Spring side of the switch
1. Lead from bridge pickup
2. Unused
3. Connects to prong #2 on the spring side of the switch to join both sides
4. Connects to prong #3 (non-spring side)
Tip: Unsure of your soldering skills? Check out “Soldering 101: A Step-by-Step Guide.”
Photo 3
Solder the leads from the pickups to the blade switch, and then add a jumper wire to connect both sides of the switch to its output lug. For the jumper, use a piece of 12-gauge stranded wire. Be sure to “tin” the entire wire before you solder it onto the switch. Tinning the jumper will make it easier to solder the wire in place, and you won’t need much additional solder. Finally, solder the wire from the volume pot’s input lug to the output lug on the switch. Photo 3 shows the CRL switch with the completed wiring.
Test drive. Now it’s time to button up the Tele. Flip over the control plate and re-install the screws to secure it. (Aren’t you glad they’re in that little box?) Now you’re ready to test out your work. Your Tele should have the classic switching configurations:
• Position 1: Bridge pickup only
• Position 2: Bridge and neck pickups
• Position 3: Neck pickup only
If everything is working correctly, slap on a new set of strings to celebrate the completed project and get ready to enjoy your new switch!