Different capacitors change the sound by lowering or raising the cut-off frequency. Moving to higher values lowers the cut-off frequency and vice versa.
In last month’s column [“Cheap and Easy Bass Mods,” May 2012], we began our bass-modding adventures by looking at ways to wire and configure passive pickups and potentiometers. Let’s stay with the “cheap and easy” theme this month and explore passive tone controls.
Most basses come with a treble roll-off knob. Essentially, its job is to reduce the highs in a full-range signal and simulate a dampened upright bass or darker flatwound sound. I’m not sure how many bassists actually use this control. Unlike guitar, treble isn’t the most important tonal range in a bass’ frequency spectrum, so perhaps these tone controls are on basses simply because guitars offer them and designers feel obliged to share the love.
That said, the standard tone knob resides on many basses. If this includes yours, you should either make good use of it or swap it for something better. (We’ll explore the latter in a future column.)
Meanwhile, let’s review the situation: Our signal chain starts with the pickups and their specific sonic signature. A pickup’s characteristic peak is its resonant frequency. When we use our tone controls, we essentially modify the size and position of this peak. As with all passive systems, a tone control can only reduce a part of the spectrum, but never add to it. Boosting a frequency is an exclusive feature of active electronics.
Unlike an active EQ—which can cut a specific frequency and even some surrounding ones—a passive tone control cuts only higher frequencies. The treble knob is a simple (or first degree) filter that’s formed by a resistor and a capacitor shunt to ground. Its cut-off frequency is mainly dictated by the capacitor’s value, at least for a given pickup and potentiometer combination.
A very common value is 47 nF. If you want to experiment with capacitor value, get a variety of different values (20 nF to 100 nF are usable values to start with) and test them out with your tone control. Moving to higher values lowers the cut-off frequency and vice versa.
Here’s a tip: Instead of soldering and unsoldering each capacitor to your potentiometer, solder two wires to the pot and then lead them outside the control cavity for easy access. You can then solder some clips to these wires or simply use bare wire to attach each capacitor. This trick allows you to easily audition the capacitors one after another.
You can see in the diagram how changing capacitor value is a pretty limited way to modify your bass guitar tone. Not that it doesn’t have much effect—it does—but we aren’t changing anything in the lower regions that characterize the bass spectrum.
The only way to do this and still stay passive is to use L-C filtering. An L-C filter is basically a network of capacitor, resistor, and inductor. Depending on the values and wiring, you can put a notch in your spectrum and vary its position, width, and depth. Instead of calculating the values and getting the parts on your own, I recommend looking for a commercial solution. Such L-C filters can come with a simple pot for a single frequency or rotary switches that directly dial in various presets.
One problem is that in a passive circuit, the parts interact with each other and it can get rather complicated to determine the sonic outcome. In practice, this means that an L-C filter’s tonal shaping will shift when you add in a second pickup. Though complex, the technical background is very interesting, and if you want to dig deeper, you can easily find more info on the web.
But does anyone use L-C filters? I’ve rarely had a bass with L-C-filtering on my workbench or seen it anywhere out in the wild. For me, L-C filtering is too variable and doesn’t provide enough visual information to be useful, especially onstage when you need to act fast.
The passive tone pot can tame an aggressive sound or let you quickly adjust to the sonic demands of different playing styles, and it’s always right at your fingertips. But other than that, you can do more effective sonic shaping by working with controls on your amp, tweaking your pickups, or using an active tone control.
Before you label me as someone who always cranks everything wide open, I’ll leave you with a short teaser for the next column: Where is your place in the mix and what strategy gets you there?
Heiko Hoepfinger is a German
physicist and long-time bassist, classical
guitarist, and motorcycle enthusiast. His
work on fuel cells for the European orbital
glider Hermes got him deeply into modern
materials and physical acoustics, and
led him to form BassLab (basslab.de)—a
manufacturer of monocoque guitars and basses. You can
reach him at
chefchen@basslab.de..
Loopers can be complex enough to make beginners cry. They are fun if you have time to venture for whole weeks down a rabbit hole. But a looper that bridges the functionality and ease-of-use gap between the simplest and most maniacal ones can be a sweet spot for newbies and seasoned performers both. The JamMan Solo HD lives squarely in that zone. It also offers super-high sound quality and storage options, and capacity that would fit the needs of most pros—all in a stomp just millimeters larger than a Boss pedal.
Fast Out of the Blocks
Assuming you’ve used some kind of rudimentary looper before, there’s pretty decent odds you’ll sort out the basic functionality of this one with a couple of exploratory clicks of the footswitch. That’s unless you’ve failed to turn down the rhythm-level knob, in which case you’ll be scrambling for the quick start guide to figure out why there is a drum machine blaring from your amp. The Solo HD comes loaded with rhythm tracks that are actually really fun to use and invaluable for practice. In the course of casually exploring these, I found them engaging and vibey enough to be lured into crafting expansive dub reggae jams, thrashing punk riffs, and lo-fi cumbias. Removing these tracks from a given loop is just a matter of turning the rhythm volume to zero. You can also create your own guide rhythms with various percussion sounds.
Backing tracks aside, creating loops on the Solo HD involves a common single-click-to-record, double-click-to-stop footswitch sequence. Recording an overdub takes another single click, and you hold the footswitch down to erase a loop. Storing a loop requires a simple press-and-hold of the store switch. The sizable latching footswitch, which looks and feels quite like those on Boss pedals, is forgiving and accurate. This has always been a strength of JamMan loopers, and though I’m not completely certain why, it means I screw up the timing of my loops a lot less.
Many players will be satisfied with how easy this functionality is and explore little more of the Solo HD’s capabilities. And why not? The storage capacity—up to 35 minutes of loops and 10 minutes for individual loops—is enough that you can craft a minor prog-rock suite from these humble beginnings. Depending on how economical your loops are, you can use all or most of the 200 available memory locations built into the Solo HD. But you can also add another 200 with an SD/SDHC card.Deeper into Dubs
Loopers have always been more than performance and practice tools for me. I have old multitrack demos that still live in the memory banks of my oldest loopers. And just as with any demos, the sounds you create with the Solo HD may be tough to top or duplicate, which can mean a loop becomes the foundation of a whole recorded song. The Solo HD’s tempo and reverse features, which can completely mutate a loop, make this situation even more likely. The tempo function raises or lowers the BPM without changing the pitch of the loop. As a practice tool, this is invaluable for learning a solo at a slower clip. But drastically altered tempos can also help create entirely new moods for a musical passage without altering a favorite key to sing or play in. Some of these alterations reveal riffs and hooks within riffs and hooks, from which I would happily build a whole finished work. The reverse function is similarly inspiring and a source of unusual textures that can be the foundation for a more complex piece.
HD, of course, stands for high definition. And the Solo HD’s capacity for accurate, dense, and detail-rich stacks of loops means you can build complex musical weaves highlighting the interaction between overtones or timbre differences among other effects in your chain. I can’t remember the last time I felt like a looper’s audio resolution was really lacking. But the improved quality here lends itself to using the Solo HD as a song-arranging tool—and, again, as a recording asset, if you want a looped idea to form the backbone of a recording.
The Verdict
With a looper, smooth workflow is everything. And though it takes practice and some concentration in the early going to extract the most from the Solo HD’s substantial feature set, it is, ultimately, a very intuitive instrument that will not just smooth the use of loops in performance, but extend and enhance its ability as a right-brain-oriented driver of composition and creation.
The Warm Bender dishes these sounds with ease and savage aplomb. Outwardly, it honors the original MkII—a good way to go given that the original Sola Sound unit is one the most stylish effects ever built. But the 3-transistor NOS 75 MkII is only one of the Warm Bender’s personalities. You can also switch to a 2-transistor NOS 76 circuit, aka the Tone Bender MkI. There’s also a silicon 3-transistor Tone Bender circuit, a twist explored by several modern boutique builders. Each of these three voices can be altered further by the crown-mounted sag switch, which starves the circuit of voltage, reducing power from 9 to 6 volts. From these three circuits, the Warm Bender conjures voices that are smooth, responsive, ragged, mean, mangled, clear, and positively fried.
The Compact Wedge Edge
Warm Audio, quite wisely, did not put the Warm Bender in an authentically, full-size Tone Bender enclosure, which would gobble a lot of floor space. But this smaller, approximately 2/3-scale version, complete with a Hammerite finish, looks nearly as hip. It’s sturdy, too. The footswitch and jacks are affixed directly to the substantial enclosure entirely apart from the independently mounted through-hole circuit board, which, for containing three circuits rather than one, is larger and more densely populated than the matchbox-sized circuit boards in a ’60s Tone Bender. Despite the more cramped quarters, there’s still room for a 9V battery if you choose to run it that way. Topside, there’s not much to the Warm Bender. There’s a chicken-head knob for output volume, another for gain, and a third that switches between the NOS 76, NOS 75, and silicon modes. Even the most boneheaded punk could figure this thing out.
A Fuzz Epic in Three Parts
Most Warm Bender customers will find their way to the pedal via MkII lust. If you arrive here by that route you won’t be disappointed. The Warm Bender’s NOS 75 setting delivers all the glam-y, proto-metal, heavy filth you could ask for. It sounded every bit as satisfying as my own favorite MkII clone save for a hint of extra compression that falls well within the bounds of normal vintage fuzz variation. My guess is that when you’re ripping through “Dazed and Confused” you won’t give a hoot.
“There’s more color and air in the NOS 76 mode.”
If the NOS 75 circuit suffers by comparison to anything, it’s the 2-transistor friend next door, the NOS 76. The lower-gain NOS 76 mode is, to my ears, the most appealing of the three. It’s the most dynamic in terms of touch response and guitar volume attenuation and delivers the clearest clean tones when you use either technique. There’s more color and air in the NOS 76 mode, too. Paired with a neck-position single-coil, it’s an excellent alternative for Hendrix and Eddie Hazel low-gain mellow fuzz that’s more like dirty overdrive. The silicon mode, meanwhile, lives on the modern borderlands of the ’60s-fuzz spectrum. It’s super-aggressive and focused, which can be really useful depending on the setting, but lo-fi, spitty, and weird when starved of voltage via the sag switch. It’s deviant-sounding stuff, but extends the Warm Bender’s performance envelope in useful ways, particularly if you hunt for unique fuzz tones in the studio.
There’s a widely accepted bit of wisdom that says most germanium fuzzes sound lousy unless you turn up everything all the way and use your guitar controls to tailor the tone. This is partly true, especially with a Fuzz Face. But in general, I respectfully disagree and present the Warm Bender as exhibit A in this defense. The gain and volume controls both have considerable range and fascinating shades of fuzz within that can still rise above the din of a raging band.
The Verdict
Some potential customers might balk at the notion of a $199 vintage-style fuzz made in China—no matter how cool it looks. But the Warm Bender looks and feels well made. The sound and tactile sensations in the three circuits are truly different enough to be three individual effects, and $199 for three fuzz pedals is a sweet deal—particularly when consolidated in a stompbox that looks this cool. There is a lot of variation in old Tone Benders, and how these takes on the circuits compare to your idea of true vintage Tone Bender sound will be subjective. But I heard the essence of both the MkI and MkII here very clearly and would have no qualms about using the Warm Bender in a session that called for an extra-authentic mid-’60s fuzz texture.
Walrus Audio’s Monumental Harmonic Stereo Tremolo is far from the only modern tremolo pedal that offers stereo panning. And it’s one of many that digitally approximates the elastic, phasey sound of brown-panel Fender harmonic tremolo. But the Monumental’s economical design and compact dimensions conjure memories of PN-2s I’ve known and missed. It brims with features an old PN-2 user could only dream of in the midst of a stereo amp reverie: the harmonic tremolo, a more traditional optical tremolo-style voice, the ability to blend the two, six wave shape options, and a subdivision switch that enables precise rhythmic variations on any given modulation pattern.
Rhythms Carved in Rock
The Monumental is, as any Walrus-watcher will know, is an evolution of theMonument, which was built around harmonic and optical-inspired tremolo voices, and features tap-tempo, subdivisions, and five waveform types. So, the big news here is the stereo capacity, presets, and the ability to blend the harmonic and optical tremolo types. You’ll pay 60 extra bucks for these extended capabilities. But if you really get into using tr-molo to its fullest potential, these are no small matters.
“The big news here is the stereo capacity, presets, and the ability to blend the harmonic and optical tremolo types.”
The Monumental uses the same-sized enclosure as the Monument V2. The only real drawback from this layout is the proximity of the tap-tempo switch to the bypass, and, as I was reminded at a jam last week, I for one, can easily miss my footswitch target if I’m deeply involved in a musical moment. That issue aside, the Monumental is impressive for the way it accommodates stereo in and out jacks, a tap and expression pedal jack, six knobs for volume, wave shape, stereo pan spread, rate, depth, and the optical/harmonic blend. The subdivision button is situated just below these and is easy to access and operate. None of it, save for the footswitches, feels cramped or difficult to navigate.
Soaring Skyward
It’s good that Walrus added presets to the Monumental, because while it can often seem subtle, the deeper you venture into the possible textures, the more detail and difference you hear among them. Waveforms like the square and sine wave sound great at low- and medium-depth settings. Other options benefit from a more-aggressive depth setting. I tended to like the optical and harmonic tremolo voices in their purest forms, but you can find many intricacies to probe and unravel in the blended settings. Some of those differences might go missing in the wash of a dense arrangement, but when they breathe in more spacious musical settings they are lovely. This is especially true when you use the pedal in stereo.
If you don’t intend to use the Monumental in stereo, you should carefully consider whether the presets and blendable voices merit the extra expenditure. For many, they will. But using the Momumental in mono alone means missing out on some of the pedal’s most infectious sounds. While square, sine, sawtooth, and random waveforms sound particularly exciting here, the other waveform types bubble and percolate all over the stereo field, often sounding percussive in optical mode and woozy in harmonic settings. Maximum depth settings sound particularly immersive. You can also enhance the effects of a dramatic stereo spread by equalizing your two amps differently. I boosted the bass and removed most of the treble from a black-panel Fender and did the inverse with a Vox-style amp for my stereo experiments. The resulting combination of detailed pick attack, strong transients, and peaky top-end popping over a fat, rubbery foundation sounded liquid and surreal—even with the pronounced treble peaks in the mix—making an already basically rich tremolo voice sound extra three-dimensional. By the way, yes, I tried the “How Soon Is Now” riff through a stereo setup. And yep, it sounded fantastic.
The Verdict
At $279, you will want to ask yourself how much tremolo you intend to use before you invest in the Monumental. There are certainly simpler ways to swamp-rock. The Monumental also lives at the more expensive end of its category—coming in a little pricier than pedals like the Keeley Hydra and the crazy-feature-rich EHX Super Pulsar. But there’s no contesting the high quality of this USA-made pedal or the thoughtful way the sounds within were conceived. And studio rats and texture obsessives that love the sensation of swimming in a stereo field may find the Monumental worth every penny.
Walrus Audio Monumental Stereo Harmonic Tap Tremolo - Orange
Unlike the simplest sustain pedals, the Layers enables the player to significantly mutate sustained notes and textures. You can add blends of delay and chorusing that aren’t perceptibly either effect, which creates uncommon-sounding stacks and waves of guitar sound. The Layers pedal takes practice to use with precision, but even partial command of its time-warping capabilities makes it rewarding to use, and it’s relatively easy to dial in chaotic—or fluid and ordered—sustain and harmonizing effects to suit your whims.
Blink Twice If You Understand
Dive straight into Layers without a peek at the quick-start guide and you might fast end up swimming in washes of repeats and harmonic tangles. At first, it might not even be apparent what a layer is supposed to be, particularly because the delay and modulation effects can be so prominent. Essentially a layer is a snapshot of the sound you’re playing as you trigger the effect—either by pressing the soft-relay footswitch or by dynamic picking, depending on where you set the threshold control. (This type of functionality will be familiar to players that use envelope filters.) From there, you can control the length of the layer with the decay control, the wet/dry mix, and the rate at which the layer becomes audible, with the attack knob. By getting a feel for these functions, you can use Layers to predictably create droning and harmonizing accompaniment to what you play. But several additional features enable dramatic alteration of the shape and color of your layers. The “single” button allows switching between a default mode, in which as many as three layers can play concurrently, and another that allows only a single layer at a given time.
A set of secondary functions for each knob are activated by holding down either the single or sub-octave button, which primarily transposes layers down an octave. Options here include the ability to adjust the modulation time, modulation blend, delay time, diffusion (between more or less cavernous ambience), and the amount of dry signal sent to the delay effect, which makes the echoes dirtier and more prominent. The footswitch does triple duty. A single click activates a layer, clicking and holding sustains a layer for as long as you hold the switch, and clicking twice clears layers and puts the pedal in bypass. Functions like dry/wet signal splits, stereo operation, and control via external pedals are also available.Third-Eye Super Vision
The features listed here make the Layers seem more imposing than it is. As I said at the top, you may stare at the pedal a lot to see when the attack threshold is crossed or see which layers have been activated in the multi-layer mode. But the longer you work with Layers, the more you can do by feel. Getting a feel for what rate of swell and decay are right for a given guitar part can change from tune to tune, which makes the absence of presets a slight inconvenience. But it’s not terribly hard to make these adjustments in between tunes or even on the fly, when you’re comfortable. If you elect to go with a single set up and stick with it, you can still add much dynamic control depending on where you set the threshold. Configuring the pedal with a low- to medium-sensitive threshold, three available layers, conservative mix levels, and more generous delay times means you can move between gentle passages where you ride over misty, slow-fading overtone backgrounds or forceful, blown-out ones—all by varying pick intensity. It’s a much more interesting way to build quiet-to-loud dynamics than just switching on, say, an extra drive pedal and reverbs simultaneously. And that flexibility can help you respond to a live performance with extra sensitivity to the mood of a piece. (By the way, it bears mentioning that Layers is often more effective at the start of an effects chain, where it will respond most directly to your input.)
Layers can be subtle. I enjoyed using low mix levels, long decay settings, a permissive threshold, and slow-ramping rise times to create hazy harmonizing trails. I also loved the avalanches of deeply modulating, colliding, and completely unsubtle soundwaves you can slather over a still-coherent melody. Loopers will love building stacks of rising, falling, swelling, and swirling passages of all of these textures that roll like storm clouds. In fact, a two-pedal setup of Layers and a looper will make a simple guitar and amplifier weirder and more otherworldly by orders of magnitude.
The Verdict
The Layers inhabits a sweet middle ground between a simple single-function sustain pedal and overflowing loopers or multi-delays. And though you can utilize very prominent harmonizing voices, it’s generally grainer, less loaded, and more unique than a shimmer reverb. It’s these very uncommon voices and sounds, as well as a capacity for intuitive operation, that make Layers so alluring.
