We’ve all heard guitar vets pine for the days of plugging straight into an amp and getting all the tones they ever needed. No need for pedals, switchers, multi-fx boards, or tap dancing. So what stops today’s players from embracing the rigs of old? Having to push old tube amps to volume-war levels is one. But the main culprit behind their reluctance to rely on their guitar’s electronics is the muddy tones they encounter when lowering their guitar’s volume.
We’ve all experienced it. You’re reveling in the harmonically rich tones of a cranked amp, you roll the guitar’s volume back for some cleaner rhythm work, and everything changes. Where did all of your glorious tone and treble response go?
The reason your tone lost its top-end sparkle is that an electric guitar’s electronics can act as a low pass filter. Think of it this way, your guitar’s volume potentiometer is a variable resistor. As you turn the volume down, it introduces more resistance into the signal and sends it to ground, allowing less to pass through. Pots with different tolerances, tapers, and impedances all have a significant effect on this interaction, often dumping your highs along with your level.
And pots are just one factor in this phenomenon. Today, guitarists often live and die by their massive pedal collections, in-depth switching systems, and modeling units. Every item in these signal chains adds another sonic barrier, chipping away at the inspiring and elusive touch response of your favorite head or combo. From your pedals and cables to your amp’s input section, every step of the process has a say in how you sound.
Luckily, there are as many fixes for treble loss as there are causes. And none are as popular – or as misunderstood – as adding a simple treble bypass filter – most commonly called a treble bleed modification – to your guitar.
At its core, a treble bleed mod is the simple (and completely reversible) addition of a capacitor, on its own or paired with a resistor, to your guitar’s volume pot. That’s all it takes to ensure your treble “bleeds” through, no matter where you have your volume control. Now, a simple twist of your volume knob takes you from driven, cranked-amp tones to glassy cleans, all while retaining your top-end detail. And best of all, a treble bleed is one of the most inexpensive and easiest (if you know how to solder electronics) guitar mods out there.
But before you grab your guitar and start soldering, there are some important things you need to know. Most importantly, there are many different ways to wire a treble bleed and even more options in capacitors and resistors. Let’s take a look at three of the most popular treble-bypass arrangements (TBA) we see around Seymour Duncan to help clear the air.
“Cap Only” wired with 1 M Volume Potentiometer
In the 1960s, Fender started installing this circuit on their Telecasters. By combining the 1000 pF capacitor with a volume potentiometer rated at a full 1 Meg, they succeeded in maintaining top-end detail. But it also gave the already thinner-sounding Tele an ice-pick treble at full volumes and a thin tone at lower volumes.
Players soon found other circuits that offered a better balance. One of the most popular is the “cap only” mod. Just add the capacitor to your guitar’s stock volume pot, and you have an effective and simple fix.
The only downside to the “cap only” mod is that it tends to roll off lows, maintaining clarity, but at the expense of a bit of warmth as your volume is reduced. This isn’t necessarily a bad thing. In fact, this is the factory treble bleed mod you’ll find on thousands of Paul Reed Smiths. It’s also incredibly useful with muddy-sounding neck humbuckers.
Capacitor and Resistor wired in parallel
Because many players prefer their treble and bass to roll off simultaneously, it’s often preferable to add a 150k-ohm resistor in parallel with the capacitor. As promised, your high- and low-end rise and fall in concert, keeping your tone intact regardless of volume knob position.
If there is a drawback to this simple circuit, it’s that it can have a radical effect on the sweep of your volume knob. The volume will decrease gradually throughout most of the range. But your output may drop suddenly toward the end of the range, making fine-tuning your sound more difficult.
Capacitor and Resistor wired in series
Love the tone of a treble bleed wired in parallel, but can’t live with the volume sweep? Series wiring – also known as the Kinman treble bleed – is for you. This circuit is extremely popular, as it protects your treble response nearly as well as parallel wiring, but maintains a familiar volume sweep.
In this setup, the values of your chosen capacitor and resistor are incredibly interactive. So we highly recommend doing your research and giving several combinations a try. But here’s what we recommend.
1000-1500 pF Capacitor: Lower values = higher frequencies, higher values = lower frequencies
100-330k-ohm Resistor: lower impedances are brighter, higher impedances are darker
So which is the right treble bleed mod for your guitar? Like all things tone, that depends on your guitar, your rig, and your ears. Because every link in your chain has an impact on how your guitar’s volume pot performs, every one of your guitars may require a different circuit. It’s up to you to find the one that works best for each.
However, as we’ve stated above, treble bleed modifications are among the easiest and most inexpensive to perform. So go ahead, pick up a bunch of different caps, resistors, and pots, then mix and match to your heart’s desire. We’re confident that you’ll land on the perfect pairing for every one of your electrics.
Now that you’ve chosen and installed the perfect treble bleed for your guitar, go plug into a cranked amp and give the volume knob a whirl. You’ll immediately understand what those old-school guitar slingers are raving about. And treble bleeds also work great with your favorite touch-responsive drive pedals – like the Seymour Duncan Forza and Palladium Gain Stage.
Not comfortable with working on your guitar electronics (or wish to keep your warranty intact)? Then we highly recommend having an authorized luthier take care of the work. But if these types of mods are no problem, you’ll love SeymourDuncan.com’s deep selection of wiring diagrams, tech tips, and tonal know-how.
As always, you can give us a call at (805) 964-9610 or email with any other questions you may have. We’d love to help you turn your guitar into the versatile tone machine it deserves to be.