The Complete Guide to Guitar Tone Capacitors
What a tone cap does, how to read its markings, and how to choose and wire the right one for your guitar.
Roll your tone knob back and the sound turns warm, round and vocal. That change comes from one small part: the tone capacitor. It costs less than a set of strings, but its value decides how dark your guitar can go and how the tone knob feels across its sweep.
Capacitors can look confusing at first, with codes like "473K" and units like µF, nF and pF. This guide explains what a tone cap does, how to read the markings, how to choose the right value and type, and the three common ways to wire one.
What a tone capacitor does
A capacitor passes high frequencies easily and blocks low ones. In a guitar, the tone cap and the tone pot sit between your signal and ground, which makes a simple treble filter. Highs that take that path drain away to ground instead of reaching your amp.
- Tone on 10: the tone pot's full resistance (250K or 500K) sits in front of the cap, so very little treble escapes. Your guitar sounds close to its natural brightness.
- Turning it down: the resistance drops, and more and more treble leaks to ground. The sound gets warmer and darker.
- Tone on 0: only the capacitor is left in the path. This is where the cap value matters most, because it sets how dark the guitar can get.
The tone cap changes your sound mainly when the tone knob is turned down. With the tone on 10, the pot value and your pickups have a much bigger effect than the capacitor.
How to read a capacitor
Most film capacitors print their maker, series, voltage, value, tolerance and date right on the body. Here's how to decode a common orange drop cap.
The three-digit code
The value is usually printed as a three-digit code in picofarads (pF). The first two digits are the value and the third digit tells you how many zeros to add.
Guitar caps are usually described in microfarads (µF). Keep these in mind: 1µF = 1,000nF = 1,000,000pF. So a 0.022µF cap is the same as 22nF or 22,000pF.
| Code | µF (microfarad) | nF (nanofarad) | pF (picofarad) |
|---|---|---|---|
| 102 | 0.001 | 1 | 1,000 |
| 222 | 0.0022 | 2.2 | 2,200 |
| 332 | 0.0033 | 3.3 | 3,300 |
| 103 | 0.01 | 10 | 10,000 |
| 153 | 0.015 | 15 | 15,000 |
| 203 | 0.02 | 20 | 20,000 |
| 223 | 0.022 | 22 | 22,000 |
| 333 | 0.033 | 33 | 33,000 |
| 473 | 0.047 | 47 | 47,000 |
| 503 | 0.05 | 50 | 50,000 |
| 683 | 0.068 | 68 | 68,000 |
| 104 | 0.1 | 100 | 100,000 |
203 and 503 aren't standard values, but they're common on guitar caps (0.02µF and 0.05µF, as found in many vintage Fenders).
How to choose, step by step
Work through these five points in order. The value shapes your sound the most; the rest decide build quality and whether the cap fits.
Look at the cap already in your guitar and read its code. If you like how your tone knob works, buy the same value. If it gets too muddy or not dark enough, go one step up or down the scale. Not sure? Send us a photo and we'll help.
01Capacitance value
A higher value cuts more treble, so the guitar gets darker as you roll the tone down. A lower value cuts less, so the sound stays clearer and brighter. As a rule, single-coils use higher values and humbuckers use lower ones, because humbuckers already sound warmer.
| Value | Typically used with | With the tone rolled down |
|---|---|---|
| 0.1µF (104) | Some vintage-style basses, players after a very dark sweep | Darkest, thick and muffled |
| 0.05µF / 0.047µF (503 / 473) | Single-coils: Strat, Tele, P-Bass, Jazz Bass | Warm and round, the classic Fender sound |
| 0.033µF (333) | HSS guitars, or players who find 0.047 too dark | A middle ground |
| 0.022µF (223) | Humbuckers: Les Paul, SG, most HH guitars | Smooth "woman tone" without going muddy |
| 0.015µF / 0.01µF (153 / 103) | Bright humbuckers, subtle tone controls | Gentle treble cut |
02Capacitor type
The type describes what the capacitor is made of, called the dielectric. All of these work well in a tone circuit; the right choice usually comes down to stability, size, looks and whether you want a vintage-correct part.
- Ceramic disc
- Small and inexpensive. Used in many vintage and modern Fenders. Fine for most players, but values can drift more than film types.
- Film (polyester or polypropylene)
- Stable, consistent and long-lasting. Orange drop caps are the best-known example. A great all-round upgrade.
- Polyester tube
- Mylar caps with leads at each end, as seen in many vintage Gibsons and Fenders. Easy to fit between lugs.
- Paper-in-oil (PIO)
- Vintage-style caps prized for originality in classic builds. Usually larger and more expensive.
Changing the value makes a clear, easy-to-hear difference. Changing the type at the same value is far more subtle. Choose the value for your sound first, then the type for build quality, size or vintage looks.
Choose the value for your sound. Choose the type for quality, fit and looks.
03Voltage rating
A passive guitar signal is only a fraction of a volt, so any rating you'll find, from 50V up to 600V, is more than enough. A higher rating doesn't change the tone, but it usually makes the cap physically bigger. Choose the rating that gives you a size that fits.
04Tolerance
Tolerance is how close the real value is to the printed one. It's shown as a letter after the code, as in "473K".
| Code | Tolerance | Example: 0.022µF cap measures |
|---|---|---|
| F | ±1% | 0.0218–0.0222µF |
| J | ±5% | 0.0209–0.0231µF |
| K | ±10% | 0.0198–0.0242µF |
| M | ±20% | 0.0176–0.0264µF |
K (±10%) is the most common and works perfectly in a tone circuit. Tighter tolerances are useful if you want two guitars, or two tone controls, to behave the same.
05Size and lead style
Make sure the cap fits your control cavity and reaches the lugs you need to connect.
- Radial leads
- Both leads come out of one side, as on orange drop and ceramic disc caps. Easy to mount between two lugs or on the back of a pot.
- Axial leads
- One lead at each end, as on tubular and paper-in-oil caps. Neat for running from one pot to another.
- Tight spaces
- Strat pickguards and shallow cavities favour small caps. Check the body size before ordering a large vintage-style cap.
Wiring the tone cap
There are three common ways to connect a tone cap. The first two are the modern standard and are electrically identical, so pick whichever is neater in your cavity. The third is the 1950s style.
All diagrams show the pots from the back, with the lugs pointing down.
01Modern, variation 1
The cap runs from the volume pot's input lug to the tone pot's middle lug. One outer lug of the tone pot is soldered to the pot back for ground.
02Modern, variation 2
A wire runs from the volume pot's input lug to the tone pot's middle lug. The cap goes from the tone pot's outer lug to the pot back. It works exactly like variation 1, but the cap sits neatly on the back of the tone pot.
031950s style
The cap runs from the volume pot's middle (output) lug to the tone pot's outer lug, and the tone pot's middle lug is grounded. Because the tone circuit sits after the volume control, the guitar tends to keep more of its treble as you roll the volume down, and the volume and tone knobs interact more. Many Les Paul players prefer it for that reason.
Some layouts reverse the input and output lugs on the volume pot. This is common with dual-volume controls, as on a Jazz Bass or PJ Bass. Always follow the diagram for your exact setup, make sure every metal part is properly grounded, and solder your grounds to the back of the pot. See our wiring diagrams for complete layouts.
Quick picks by guitar
Common starting points for popular instruments. Treat them as a starting point and adjust to taste.
Stratocaster
Three single-coils (SSS)
- Value
- 0.047µF (473); 0.022µF for a lighter cut
- Type
- Ceramic or film
- Wiring
- Modern
Telecaster
Two single-coils
- Value
- 0.047µF (473) or 0.05µF (503)
- Type
- Ceramic or film
- Wiring
- Modern
Les Paul & SG
Two humbuckers
- Value
- 0.022µF (223)
- Type
- Film, or paper-in-oil for vintage builds
- Wiring
- Modern or 1950s style
HSS & HH guitars
Humbucker-equipped superstrats
- Value
- 0.022µF (223) to 0.033µF (333)
- Type
- Film
- Wiring
- Modern
P-Bass
Split-coil passive bass
- Value
- 0.047µF (473); 0.1µF (104) for a darker sweep
- Type
- Ceramic or film
- Wiring
- Modern
Jazz Bass
Two single-coils, dual volume
- Value
- 0.047µF (473)
- Type
- Ceramic or film
- Wiring
- Modern; check the volume lug order
Changing pots too? See our Potentiometer Guide to match the pot value to your pickups.
Beyond the tone knob
Capacitors do more than run your tone control. These two popular mods use them to shape your sound in other ways.
Installation tips
- Direction usually doesn't matter. Film and ceramic tone caps aren't polarised, so either lead can go to either lug. Some players put the marked outer-foil end toward ground, which can slightly reduce noise.
- Photograph the old wiring first. A clear photo of where the old cap was connected is the easiest way to get it right.
- Keep leads short and tidy. Trim the leads to length and slip insulating sleeving over any bare lead that could touch another lug or the cavity shielding.
- Solder quickly. Heat the joint and get in and out. Holding the iron on a cap lead for too long can damage the capacitor.
- Test before you close up. Plug in and sweep the tone knob from 10 to 0. You should hear a smooth change from bright to warm.
Rather not solder? Choose our pre-wired solderless kits, or let us do it with our wiring services.
Frequently asked questions
What does a tone capacitor do?
Together with the tone pot, it sends high frequencies to ground. Turning the tone knob down lets more treble drain away, which makes the guitar sound warmer and darker.
What's the difference between 0.022µF and 0.047µF?
A 0.047µF cap cuts more treble, so the guitar gets darker when you roll the tone down. A 0.022µF cap cuts less, keeping more clarity. As a rule, 0.047µF suits single-coils and 0.022µF suits humbuckers.
What does 473 mean on a capacitor?
It's the value in picofarads: 47 followed by three zeros, or 47,000pF. That's the same as 47nF or 0.047µF.
Does the type of capacitor change the tone?
The value makes a clear difference. At the same value, differences between types are subtle. Most players choose the value for their sound, then the type for build quality, size or vintage looks.
Does the voltage rating matter?
Not for tone. A guitar signal is far below any common rating, so 50V to 600V caps all work. Higher-voltage caps are usually larger, so choose one that fits your cavity.
Which way round does a tone capacitor go?
Film and ceramic tone caps aren't polarised, so they work either way round. Some players connect the marked outer-foil end to ground, which can slightly reduce noise.
Find the right tone cap for your guitar
Shop ceramic, film, orange drop and paper-in-oil capacitors, or send us a photo of your wiring and we'll recommend a value.
Shop capacitorsAsk us which cap to getNeed a diagram for your exact setup? See our wiring diagrams or request a custom one.