Pedals! Despite the wide range of effects they produce, individually, they’re typically pretty straightforward devices. But as soon as you begin to assemble a chain of pedals, complicating factors seem to mount up exponentially. The inconvenient reality is that the more complex the system of pedals, the more helpful it becomes to have some basic knowledge of electronics. But failing that, a few key rules of thumb can help if you need to put together a reliable rig that facilitates (rather than impedes) creativity and musicality.
Since most guitarists don’t have degrees in electrical engineering, let’s first focus on not frying your pedals, and proceed slowly from there.
1. Powering Up
Almost all pedals need some sort of power to function. For just a pedal or two, a 9-volt battery or manufacturer-supplied AC adapter can work fine, but when assembling an entire pedalboard with several devices, a dedicated multi-output supply (like the Voodoo Labs Pedal Power II+, pictured below) is usually preferred. Unfortunately, this is where things can start to get dicey.
There are three main danger zones when powering your pedals — the voltage requirement, the current requirement, and the polarity of the connector. All must be correct or you can damage your pedal (and your supply).
In (over-)simplified terms, voltage could loosely be described as the electricity’s intensity, whereas the current is more like rate of electrical flow. Polarity specifies which direction the electricity flows into and out of the circuit.
Voltage is measured in Volts (V) and the supply should always match the pedal’s requirement exactly. If your pedal takes a 9V supply, it could be damaged (or at least malfunction) with a supply of any other voltage.
Current is rated in amperes, or for our purposes, milliamperes (mA). Your power supply needs to handle at least as much current as your pedal requires, but the spec needn’t match exactly. For example, if I have a pedal that draws 60mA of current and a supply that’s capable of outputting 100mA, I’m perfectly safe. A pedal that draws more than a supply is capable of killing the power supply, so it’s worth researching the exact numbers. But broadly speaking, distortions and boosts tend to sip power, while reverbs, delays, and anything digital tend to guzzle it.
Polarity goes one of two ways — “tip negative” or “tip positive” (for BOSS-style barrel adapters, this is sometimes called “center negative” or “center positive”). Most pedals will have a graphic near their power inlet that specifies the polarity that looks something like this:Make sure you get this correct, because incorrect polarity will usually kill your pedal, requiring expensive repair or replacement.
The problem with standards is that there are so many of them.
Since the 1980s, just enough pedals have followed one voltage and polarity convention to be dangerous — namely, the BOSS 9V barrel plug with the tip negative connection. BOSS, Ibanez, and almost all small, boutique builders will use this standard. But it is by no means universal, which makes it easy for less-informed users to get caught off-guard.
What’s especially confusing is that many pedals use the exact same barrel adapter, but a different voltage, or opposite polarity. Moogerfooger pedals, for one example, use a BOSS-style barrel connector, but are tip positive. Some versions of the Electro-Harmonix Deluxe Memory Man power adapter also use the same connector, but supply 24 volts. One false move in either case (and many others like them), and you’ve fried your pedal, so be vigilant and double check the markings!
2. Impedance Matters: When “true bypass” is false (and other stories)
Buffer, the Vampire Slayer
“True” mechanical bypass is a legitimate design choice (and marketing buzzword), but it is far from a panacea for signal integrity. Logically, it seems like it should be the most transparent — when the pedal is bypassed, it behaves as a straight wire. How could this possibly be bad?
Well, as we’ve already seen, reality in audio is rarely so intuitive! The big complicating factor is that electric guitar pickups output a high impedance signal. We’ll skip the electronics course, but you should know that high-impedance signals are very susceptible to noise, and therefore require shielded cables. Unfortunately, long, high-impedance runs of shielded cable cause signal loss due to cable capacitance, which is a fancy way of saying that your high end starts to go away. This is noticeable in most decent-quality instrument cable when lengths reach about 20 feet or more.
Now imagine a conservative, real-world scenario where you have a 10-foot cable between guitar and pedalboard, a 10-foot cable between the board and the amp, six true bypass pedals (each having 6 inches of wire between the jacks — that counts, too!) and five 1-foot cables between the pedals themselves. That adds up to 28 feet of cable between the guitar and amp with everything bypassed — more than enough to cause an audible degradation guitarists refer to as “tone sucking.”
A few decades ago, some manufacturers began implementing buffer circuitry in the bypass mode of many pedals precisely to address this issue. A quality buffer transparently lowers signal impedance so that much longer shielded runs can be made without robbing high end. But unfortunately, the story doesn’t end here. When “True Bypass” hype caught on among gearheads in the late 1990s, it grew around a kernel of truth — the partial bypass used in older wah pedals caused severe loading and “tone suck.” But somehow in the puritanical fervor that suddenly swirled, “buffered bypass” accidentally became a dirty word, too — a classic case of “just enough knowledge to be dangerous.”
The thing is, a well-implemented buffer somewhere in the chain is usually positive. A majority of true-bypass pedals can be OK, but in most cases, having at least one buffer near the beginning or end of a pedal chain will make your “everything bypassed” tone sound much more like a straight wire between guitar and amp.
The ScreaminFX blog has a great breakdown of why and when to use a buffer pedal. Here are some of their suggestions:
As with everything, there are exceptions
A certain few pedal designs, however (including old Fuzz Faces, Univox Superfuzzes, early Thomas Organ or Vox wah wah pedals, and a even few modern pedals like the Blackstone MosFet overdrive), really need to see a high-impedance input to sound their best. So make sure that you place any buffers after those pedals in your chain. Remember, even that BOSS TU-2 tuner has a buffer in it, so if you have a Superfuzz and a vintage CryBaby, make sure they’re literally the first things in your chain!
3. Signal Flow Basics
A common question from pedal neophytes is “which order should my pedals go in?” The only universal answer is “whichever sounds best to you,” but there are a number of conventions in place for good reason.
Filter effects (like wah pedals) sound their most conventional when placed before any distortion devices. This is particularly true of envelope filters, as distortion radically changes the transient envelope of a note. When a transient is clipped and distorted, the filter often won’t sweep in as satisfying a way.
Volume pedals are a judgment call. I usually like to place mine after any distortion effects, but before any time-based effects like delay or reverb. I want to be able to ride the overall level, but keep the distorted sound the same, and I want the reverb and delay trails to keep trailing off, even after I cut the volume. However, some others prefer to use a volume pedal to feed into a particularly responsive distortion pedal so they can clean up the sound by rolling back the input.
Generally time-based and modulation effects go after any distortion effects (to the point where many prefer to put them in an effects loop of an amplifier), as it tends to sound more natural that way.
However, don’t be afraid to break all of the rules and experiment! I am giving you advice that I have learned for myself over the years, but there isn’t a right or wrong with this stuff, so go ahead and reinvent the wheel!
Strymon’s blog has a couple pretty nifty set-up suggestions (with limited pedal types represented), but it’s a good thing to get used to looking at and thinking about, so check these out.
4. Putting It All Together
I have one pedalboard rig that has been on several world tours, checked into the cargo hold of literally hundreds of airplanes, and is still going strong. While one pedal died and a few others have been shuffled in and out, I believe every single signal and power interconnect is original to my initial assembly.
This all comes down to careful assembly, quality interconnects, and good strain relief.
One thing that helps is to lay your pedals out neatly, and make or buy patch cables that are as near as possible to the exact right length. Run the leads neatly and zip-tie them together for strain relief when possible. I also like to include my power cables in the zip-tie scheme, securing everything to my commercially-purchased aluminum frame board so that nothing moves or jostles in transport.
Many commercial pedalboard solutions come with industrial velcro, and I find this works quite well as a non-permanent means of securing pedals to the rig. But I’ve seen some other creative solutions, including links of bicycle chain attached to the pedal enclosures via the enclosure’s own screws, and then screwed to a wooden board. Whatever works!
It’s not always intuitive, but it is certainly possible, with a little attention, to put together a well-integrated pedalboard rig that performs optimally. As always, the more complex your rig, the more potential pitfalls, but like everything else, it gets easier with experience. Stomp away!