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.