Passive single-coil pickup systems have an inherent sonic idiosyncrasy: When you turn down the volume—even just a bit—the high-end loss is not proportionate to the volume reduction. In other words, a small cut in volume creates a far greater drop in your guitar's treble response. This is true of the Stratocaster and Telecaster, as well as many other popular models, so I'm sure you're familiar with it.
This quirk of passive electronics isn't really a big deal for all players. Many aren't bothered by it because they've simply gotten used to the sound over the years. Others really like this "problem," since it lets you coax a second tonal color from the same pickup—simply roll back the volume a tad to fatten up the tone. But a lot of guitarists (myself included) prefer to maintain an identical amount of treble at any volume setting.
Using active electronics is the only real solution to combating the "volume-versus-tone" issue—all other strategies are just a compromise. That said, compromise can lead to significant improvements. Personally, I use a compromising solution in all of my own guitars. And my favorite solution is one of the easiest mods ever: add a "treble-bleed network" between the input and output of the volume pot(s) of the guitar. This works with passive single-coils and humbuckers, but if your guitar has more than one volume control, like on a Les Paul, each volume pot needs its own treble-bleed network.
Some Background.
So, what is a treble-bleed network and how does it work? In layman's terms, it's usually a combination of a small capacitor and a resistor in parallel. Techies call this a RC network, but such systems are also called a "treble bypass filter" or TBA, for treble-bypass arrangement. You can also find variations that use only a cap, or a resistor in series with the cap.
The theory behind this little rascal appears straightforward, but it's much more complicated than it seems. So as not to slam you with theory, I'll stick to the basics, which means having to over-simplify the following explanation.
First, the good news: It's possible to calculate the values for a treble-bleed network that will work superbly in a given guitar. The bad news? The formula behind it is complex and beyond the scope of this column. There are many parameters involved in this formula, such as the number, ratio, and resistance of the pots in your guitar, the pickups, the length and capacitance of your guitar cable, the input impedance of your amp, and more. All of these must be calculated in the context of a Fletcher-Munson curve, which defines equal-loudness contours for the human ear. Doable, but really complicated!
Typically, you have to make several simulations and analyze the corresponding curve to see if it matches your goal. Such calculated networks will work wonderfully in the guitar you calculated them for, but when you change one of the parameters—like the length or type of your guitar cable, or you plug into a different amp—the treble-bleed network will stop working perfectly. That's an unavoidable fact. Because of all the parameters involved, it's easy to see why standard "one-size-fits-all" networks are an illusion.
So you can experiment to determine what you like best, based on your own gear and sonic goals, I'll describe the different types and possible value ranges of the components. Because the range of these components is very limited, at minimum you'll achieve good results. But if you want great results, it's important to realize you'll have to experiment with each individual guitar, and this includes a lot of component swapping.
When you roll down the volume, the treble-bleed network starts to filter out some bass frequencies, making the highs more prominent.
The Details.
When you roll down the volume, the treble-bleed network starts to filter out some bass frequencies, making the highs more prominent. It won't boost anything (treble, in this case) because a passive device can only filter out certain frequencies. The networks are always connected between the input and output of the volume control, as shown in Fig. 1.
There are basically three different types of treble-bleed networks (Fig. 2), and we'll examine each of them. On the left is "cap only," which isn't a true network because it's a capacitor without a resistor. Fender made this version popular in the '60s when they started installing a 1000 pF cap on Telecaster volume controls. Together with the 1M pots they used at this time, the sonic result was kind of creepy ... thin and bright.
This value is still popular today in many one-size-fits-all solutions. This circuit has one problem: As the volume is turned lower, more of the higher frequencies will predominate—even to the point where the guitar starts to sound very "tinny" as the volume approaches zero. Depending on what you're after sonically, this can be a good thing or not. If you want to experiment with this cap-only configuration, good working values are from 220 pF up to 1500 pF.
Our second type of treble-bleed network is shown in the center of Fig. 2. This consists of a cap with a resistor in parallel. This is the version you'll find in most treble-bleed networks. A very popular combination is a 1000 pF cap with a 150k-ohm resistor in parallel. This works for almost any guitar, when it comes to a one-size-fits-all solution.
Fig. 2
The cap-with-resistor-in-parallel version can be superior to the cap-only method because, as you turn the volume lower, 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 when the two values are not carefully matched to each other. Good working values to try are from 220 pF up to 1500 pF for the cap, and 100k-ohm up to 330k-ohm for the resistor.
Our third treble-bleed network, shown on the right, consists of a cap with a resistor in series. This configuration became popular in the '90s when Australian luthier Chris Kinman started to use a 1200 pF cap and a 130k-ohm resistor in series for his guitars. This scheme is regarded by many to be the best of the three versions, because it seems to solve the problem of the volume pot taper and the tinny sound. Even Fender uses it now. Their system employs a 1000 pF cap and a 130k-ohm resistor, and is dubbed the Fender Tone Saver. Values you should try are 470 pF up to 1500 pF for the cap, and 100k-ohm up to 330k-ohm for the resistor.
Regarding the two components, here's a rule of thumb: Brightness is determined by the resistor's value (less ohms yields more highs), but the frequencies that are present are determined by the cap's value—the lower the value, the higher the frequencies, and conversely, the higher the value, the lower the frequencies.
Into the sound lab. To conduct your own treble-bleed network 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 for fast access, you can easily try every combination of cap and resistor. (Be sure to take notes.)
After you find your favorite combination, remove the two wires and permanently install it to the volume pot. Remember, what you choose may be very different from another player. Some like more high end (this is often due to a dark-sounding amp), while others prefer more midrange to get a punchy sound. It's worth taking the time to try several combinations. This simple circuit can turn a muddy-sounding guitar into an articulate one—even with tons of distortion—because the tone will clean up when you roll back the volume.
I can't advise you what to use—you need to explore this yourself or let an experienced tech calculate your personal treble-bleed network, based on your specific rig. Many guitarists like the cap-only version for Strats and Teles, while others prefer a cap and a resistor in parallel. The resistor-in-parallel and resistor-in-series schemes perform more-or-less equally, but the parallel version offers more highs when you turn down the volume. Again, this can be positive or negative, depending on your pickups and amp.
Okay, that's it for now. Until next time ... keep on modding!
[Updated 9/10/21]
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- The Fascinating Peavey T-60 Tone Circuit - Premier Guitar ›
- Mod Garage: Three Ways to Wire a Tone Pot - Premier Guitar ›
- Mod Garage: The Fender Greasebucket Tone Circuit - Premier Guitar ›
- The Fascinating Peavey T-60 Tone Circuit - Premier Guitar ›
- Assessing a Pickup’s Polarity and Phase ›
Naturally, every recording Eddie Van Halen ever played on has been pored over by legions of guitar players of all styles. It might seem funny, then, to consider EVH solos that might require more attention. But your 100 Guitarists hosts have their picks of solos that they feel merit a little discussion. Some of these are deep cuts—get ready for some instrumental bonus tracks and Van Halen III mentions—and some are among the biggest radio hits of their time. Just because their hits, though, doesn’t mean we don’t have more to add to the conversation.
We can’t cover everything EVH—Jason has already tried while producing the Runnin’ With the Dweezil podcast. But we cover as much as we can in our longest episode yet. And in the second installment of our current listening segment, we’re talking about new-ish music from Oz Noy and Bill Orcutt.
Tinkering with theSDE-3 Dual Digital Delay suggested a similar, possibly enduring appeal. As an evolution of the Roland SDE-3000rack unit from the 1980s, it’s a texture machine, bubbling with subtle-to-odd triangle LFO modulations and enhanced dual-delay patterns that make tone mazes from dopey-simple melodies. And with the capacity to use it with two amps in stereo or in panning capacity, it can be much more dimensional. But while the SDE-3 will become indispensable to some for its most complex echo textures, its basic voice possesses warmth that lends personality in pedestrian applications too.
Tapping Into the Source
Some interest in the original SDE-3000 is in its association with Eddie Van Halen, who ran two of them in a wet-dry-wet configuration, using different delay rates and modulation to thicken and lend dimension to solos. But while EVH’s de facto endorsement prompted reissues of the effect as far back as the ’90s, part of the appeal was down to the 3000’s intrinsic elegance and simplicity.
In fact, the original rack unit’s features don’t differ much from what you would find on modern, inexpensive stompbox echoes. But the SDE-3000’s simplicity and reliable predictability made it conducive to fast workflow in the studio. Critically, it also avoided the lo-fi and sterility shortcomings that plagued some lesser rivals—an attribute designer Yoshi Ikegami chalks up to analog components elsewhere in the circuit and a fortuitous clock imprecision that lends organic essence to the repeats.
Evolved Echo Animal
Though the SDE-3 traces a line back to the SDE-3000 in sound and function, it is a very evolved riff on a theme. I don’t have an original SDE-3000 on hand for comparison, but it’s easy to hear how the SDE-3 bridges a gap between analog haze and more clinical, surgical digital sounds in the way that made the original famous. Thanks to the hi-cut control, the SDE-3’s voice can be shaped to enhance the angular aspect of the echoes, or blunt sharp edges. There’s also a lot of leeway to toy with varied EQ settings without sacrificing the ample definition in the repeats. That also means you can take advantage of the polyrhythmic effects that are arguably its greatest asset.
“There’s a lot of leeway to toy with varied EQ settings without sacrificing the ample definition in the repeats.”
The SDE-3’s offset control, which generates these polyrhythmic echoes, is its heart. The most practical and familiar echos, like quarter, eighth, and dotted-eighth patterns, are easy to access in the second half of the offset knobs range. In the first half of the knob’s throw, however, the offset delays often clang about at less-regular intervals, producing complex polyrhythms that are also cool multipliers of the modulation and EQ effects. For example, when emphasizing top end in repeats, using aggressive effects mixes and pitch-wobble modulation generates eerie ghost notes that swim through and around patterns, adding rhythmic interest and texture without derailing the drive behind a groove. Even at modest settings, these are great alternatives to more staid, regular subdivision patterns. Many of the coolest sounds tend toward the foggy reverb spectrum. Removing high end, piling on feedback, and adding the woozy, drunken drift from modulation creates fascinating backdrops for slow, sparse chord melodies. Faster modulations throb and swirl like old BBC Radiophonic Workshop sci-fi sound designs.
By themselves, the modulations have their own broad appeal. Chorus tones are rarely the archetypal Roland Jazz Chorus or CE type—tending to be a bit darker and mistier. But they do a nice job suggesting that texture without lapsing into caricature. There are also really cool rotary-speaker-like textures and vibrato sounds that offer alternatives to go-to industry standards.
The Verdict
The SDE-3’s many available sounds and textures would be appealing at $219—even without the stereo and panning connectivity options, a useful hold function, and expression pedal control that opens up additional options. The panning capabilities, in particular, sparked all kinds of thoughts about studio applications. Mastering the SDE-3 takes just a little study—certain polyrhythms can be dramatically reshaped by the interactivity of other controls and you need to take care to achieve identical results twice. But this is a pedal that, by virtue of its relative simplicity and richness and breadth of sounds, exceeds the utility of some similarly priced rivals, all while opening up possibilities well outside the simple echo realm
Reader: T. Moody
Hometown: Myrtle Beach, South Carolina
Guitar: The Green Snake
Reader T. Moody turned this Yamaha Pacifica body into a reptilian rocker.
I have always loved the reverse headstock, simply because nothing says 1987 (the best year in the history of the world) like a reverse headstock. The pickups are both Seymour Duncan—an SH-1N in the neck position and TB-4 in the bridge, both in a very cool lime green color. Right when these pickups got listed, the Buy It Now button once again lit up like the Fourth of July. I am a loyal disciple of Sperzel locking tuners and think Bob Sperzel was a pure genius, so I knew those were going on this project even before I started on it. I also knew that I wanted a Vega-Trem; those units are absolutely amazing.
When the body arrived, I thought it would be cool to do some kind of burst around the yellow so I went with a neon green. It turned out better than I imagined. Next up was the shaping and cutting of the pickguard. I had this crocodile-type, faux-leather material that I glued on the pickguard and then shaped to my liking. I wanted just a single volume control and no tone knob, because, like King Edward (Van Halen) once said, “Your volume is your tone.”
T. Moody
I then shaped and glued the faux-leather material in the cavity. The tuning knobs, volume knob, pickguard, screws, and selector switch were also painted in the lemon-lime paint scheme. I put everything together, installed the pickups, strung it up, set it up, plugged it in, and I was blown away. I think this is the best-playing and -sounding guitar I have ever tried.
The only thing missing was the center piece and strap. The latter was easy because DiMarzio makes their ClipLock in neon green. The center piece was more difficult because originally, I was thinking that some kind of gator-style decoration would be cool. In the end, I went with a green snake, because crocodiles ain’t too flexible—and they’re way too big to fit in a pickup cavity!
The Green Snake’s back is just as striking as the front.
