Treble Bleed Circuit – What is it and do I need it?

Have you ever noticed that when you turn down the volume on your guitar or bass that your signal loses some treble and starts to sound muddy and lifeless? Many guitarists resort to using the volume knob as a simple way to mute their guitar. Personally, I like to use it to control the gain in my signal. I can go from crystal clear clean tones to full overdrive with the sweep of my volume control.

What causes the loss in treble when we turn down the volume knob on our guitars?

When the volume pot is lowered from ’10’, resistance is added in series with the signal output of the pickup. This resistance, combined with the cable capacitance, and the pickup itself forms a low pass filter, allowing lower frequencies through but blocking some of the higher frequencies. The resultant tone for most people becomes unusable.

There is a simple and very cheap fix for this problem, and it is well worth doing. The solution is to install a treble bleed circuit to your guitar, which can be either a single capacitor or a combination of a capacitor and a small resistor. A capacitor wired in parallel with the terminals on your volume pot will allow the high frequencies through when the volume is reduced. The capacitance value of the capacitor will determine the cut off point for the frequencies allowed through. Wiring a resistor in series or parallel with the capacitor will help to control the brightness. To install this circuit yourself you will need some basic tools, a soldering iron, solder, the necessary components and the confidence to use them. If you are not confident in performing your own guitar modifications, any guitar tech should be able to do this.

A series capacitor/resistor and a parallel capacitor/resistor
Series capacitor/resistor (left) and parallel capacitor/resistor (right).

Why don’t guitars have treble bleed circuits installed from new?

Good question. Probably because it didn’t occur to them to do it back in the day and why bother now when they can sell it for a high price as a separate aftermarket option. There are a few exceptions, but American manufacturers have yet to make it a standard feature whereas some smarter Asian manufacturers now install it as standard in many of their guitars.

What do I need?

Different guitars will require different value components in their treble bleed circuits mainly due to the difference in their pickups. Determining which components to use in some cases can require some trial and error with different value capacitors and resistors until you get a result that sounds good to you. Here I will show some of the different circuits and component values used, to guide you in the right direction.

The Circuits

Single Capacitor

The simplest treble bleed circuit is a single capacitor wired across two of the terminals of the volume potentiometer.

Pros: It is all that is needed for some guitars.
Cons: There isn’t enough attenuation of the high frequencies and the signal can become too bright and tinny as the volume is reduced.

Parallel Capacitor/Resistor

Wiring a resistor in parallel with the capacitor will help to balance the signal. As you reduce the volume, the higher frequencies don’t dominate. The problem with this circuit is that it affects the taper of the volume pot in a negative way.

Pros: It is works on most guitars.
Cons: Changes the taper of the volume pot. Requires correct value to components to work properly.

Series Capacitor/Resistor (Kinman circuit)

This circuit consists of a capacitor wired with a resistor in series. This configuration became popular in the ’90s when Australian luthier Chris Kinman started to use a capacitor and resistor in series for his guitars. Regarded by many to be the best of the three versions, because it solves the problem of the volume taper and the tinny sound.

Pros: Solves the volume taper and tinny tone issues.
Cons: Requires correct value to components to work properly.

Component types and values

Capacitors store electrical energy, and their ability to store energy (capacitance) is measured in Farads. Now a 1 Farad capacitor would be a very large capacitor indeed. Most capacitors used in electrical circuits are measured in Microfarads with a 1 mF capacitor being equal to 0.001 Farads. For our circuit we require even smaller capacitors with capacitance values measured in Picofarads. 1 Picofarad is equal to 0.000000000001 F. Yes, it’s tiny. Values to try for this application range from 220 pF up to 1500 pF with 1000 pF being the most common.

Capacitors also have different voltage ratings. We need not concern ourselves with that, the signal from a guitar pickup is measured in millivolts. There are many types of capacitors available including: electrolytic, ceramic, mylar film, paper, mica and so on. Electrolytic capacitors are not suitable for treble bleeds circuits. Ceramic or film are ideal and the smaller the better, we don’t exactly have a lot of space in our control cavities.

A mylar fim capacitor and a ceramic capacitor
A mylar film capacitor (left) and a ceramic capacitor (right).
A strip of 0.25-watt resistors
A strip of 0.25-watt resistors.

Resistors are components which resist the flow of electrical current. When used in a treble bleed circuit they attenuate the high frequencies to keep the signal frequency balanced. Again, we don’t need physically large components. 0.25-watt resistors are just right. The unit of electrical resistance is the Ohm. For our purposes we would use a resistor ranging from 100 k-ohm up to 330 k-ohm.

Time to Experiment?

If you decide to conduct your own treble bleed experiments, solder two wires to the input and output of the volume pot and connect alligator clips on the other ends. If you let the two wires hang out from under the pickguard, you can easily try every combination of capacitor and resistor and see which sound right to you. Remember, tone is subjective, what works for you might not work for another.

Alternatively, you could go with more commonly used circuits some of which are in the table below.

Manufacturer Circuit Type Capacitor Resistor

Octave Doctor

Series
1000 pF (1 nF)
150 k-ohm

PRS

Single Capacitor
180 pF
None

G&L

Single Capacitor
200 pF
None

Mojo Tone

Parallel
470 pF
220 k-ohm

DiMarzio

Parallel
560 pF
300 k-ohm

Suhr

Parallel
680 pF
150k -ohm

TV Jones (single coil)

Series
1000 pF (1 nF)
150 k-ohm

TV Jones (humbucker)

Series
2000 pF (2 nF)
150 k-ohm

Seymour Duncan

Parallel
1000 pF (1 nF)
100 k-ohm

Chris Kinman

Series
1200 pF (1.2 nF)
130 k-ohm

Cort

Parallel
680 pF
150 k-ohm

Conclusion

Should you decide that a treble bleed circuit is for you, remember this: The modification is completely reversible, once installed it will not affect the tone of your guitar when the volume pot is turned all the way up (max volume). Basses and guitars with on board active circuits do not need treble bleed circuits.

The series combination of 1000 pF capacitor and 150 k-ohm resistor are recommended by many sources as a good choice for maintaining a consistent resonant peak as volume decreases.

Be wary of vendors or manufacturers who will sell you horribly overpriced components based on mythical characteristics that don’t actually exist. Expensive paper in oil capacitors, sprague orange drops and bumble bee capacitors will NOT improve your tone. If you don’t want the hassle of sourcing your own, a good guitar tech should stock the necessary components.

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15 Responses

  1. The parallel setup is weird on my old Strat… I’m gonna use the series setup when I install my new Oc Doc pups next week…

  2. Ok, first, I replaced the parallel treble bleed setup (470pF cap + 220kOhm res) with a Kinman-series setup (1000 pF cap + 150 kOhm res) first & check the sound… much better than excellent ! Then, I replaced the pickups, which were a fender replacement sent I installed a loooonnng time ago, & also rewired the switch to tie the bridge & middle pickups to the middle tone control. This old guitar about brought this old dog to tears… WOW! Which, more precisely, is to say WOW !!!!!!

  3. What would you say of this for Bass Humbuckers (on an Eastwood Vointage 4 semi-hollow body wwith two sets of humbuckers).

    Series – 1000 pF (1 nF) – 150 k-ohm

    1. Hi Jeffrey, I have never tried a treble bleed on a bass guitar. Even though I have one, the volume pot never gets turned down. If you feel that yours needs a treble bleed circuit then I would suggest starting with 1000pF and 150kohm in both series and parallel and see which works best. However, you might find that bass guitars need a different combination of capacitor and resistor to electric guitars.

  4. Question: in the series resistor/capacitor treble bleed circuit does the resistor before or after the cap, or does it matter?

      1. Indeed. Since the audio signal is “AC”, the current will be flowing both ways through the series circuit. Order doesn’t matter.

  5. I want to put my treble bleed on a spst toggle switch. (I think that’s the right kind). On/Off switch.
    I know Jesse Davey has one on his strat. I did have it wired to a push/ pull volume pot, and then I tried a push/push pot, but they both failed.
    I like being able to turn off the treble bleed when using a fuzz and rolling down the volume.
    Any particular switch needed for this?
    Thanks

    1. Hi Michael, Any single pole switch would work for your needs. It’s just a matter of wiring it in series with the treble bleed circuit to electrically isolate it from the rest of the guitar circuitry.

  6. I have been thinking of Building Custom Harmonica Mics With NOS Crystal Mic Elements I found. I wanted A simple Control Better Than Just Volume. I think This Might Do Thanks.

  7. Great article, very clear and comprehensive!

    I use the capacitor-only circuit on both of my Eccleshall guitars, but have added a couple of touches you might find useful.

    Firstly, the bleed is attached to the third leg of the tone control on both guitars. This means that as I turn down the tone, the bleed is also gradually dialled out. No need for a bleed switch.

    Secondly, one of the guitars has a single humbucker and on that one I’ve connected the bleed to the junction between the coils. Thus the treble is bled before the second coil cancels it. This gives the guitar a treble edge that it wouldn’t have if the humbucker was wired normally. The pickup also has a series/parallel switch, and the bleed works in either mode.

  8. Dobrý den jaké hodnoty by byly vhodné na zapojení kytary Vintage V100 Les Paul se snímači Wilkinson?

  9. Great, clear and very useful post! but… now I don’t know what to do!
    I have a Fender Strat with 2 single coil p.u. and 1 humbucker (bridge position).
    1 volume knob and only 1 tone knob.
    I need a treble-bleed circuit… which one is the right one?

    1. Sorry for the late response Luca. If I were in your shoes I would start by trying a treble bleed circuit more suited to humbuckers. The bridge pickup is like the most used pickup on your guitar right?

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