The assembled main PCB for the FuzzDog Moon Phase pedal kit.
Making your own pedals can be a lot cheaper than buying them — and with many of the self‑build kits now available, you won’t even need a deep knowledge of electronics.
With so many circuit schematics available online, and numerous companies offering DIY guitar pedals in kit form, there’s never been a better time to build your own stompboxes. Not only can this save you money, but you can also recreate coveted pedals that are no longer in production. You can also adapt them, for example by combining multiple effects in one bigger enclosure, or building them with a modular synth system in mind.
But what are the realities of rolling your own? In this article, I’ll explain the skills and tools you need, and discuss a recent kit‑based project, to give you a better feel for how it works in practice.
Tools, Parts & Tactics
There’s some initial outlay for tools, of course, and if you don’t have most of them already, you’re unlikely to enjoy any cost saving unless you plan on making at least a few kits (or need the tools for other jobs). You’ll need a decent 30‑50W soldering iron, ideally one that’s thermostatically controlled and has a fine conical tip. You’ll also need a multimeter (the orange-coloured device in the photo, below). These days, meters that can read capacitor values are very affordable, and as some capacitor markings can be a bit ambiguous, I’d recommend spending just that little bit more to get one. You’ll also need some small wire cutters and a ‘solder sucker’ desoldering tool, for those occasions when the solder ends up where it shouldn’t. Small pliers are useful for holding awkward components and as a heat sink when soldering. I also find a bright work light and a desk magnifier very helpful.
When assembling the final pedal, as well as screwdrivers you’ll also need spanners (or a small adjustable spanner) to tighten the nuts around the pots, footswitch and sockets. If you plan to drill your own case, you’ll also need an electric drill and a some suitable bits. The standard‑size compact pedal case that can take a battery is designated 1590B. Mini pedals that don’t have space for a battery usually reside in the narrower 1590A case.
It helps to have an organised space, with tools such as clamps, lights and magnifiers, as well as bowls for sorting components to prevent them going astray.
As long as you can follow instructions you don’t need any deep electronics knowledge, but you do need the ability to solder tidily. When you’re soldering semiconductors and chips, you need to do it quickly, too! This isn’t a soldering lesson (there are lots of good ones on YouTube) but the key thing to remember is to heat the joint first and then feed solder to it, rather than carrying solder to the joint on the iron’s tip. If you’re new to this, don’t start with anything too complex. Begin by tinning wires and seeing if you can make a tidy job of wiring an XLR or jack plug. If you can do that, you’re probably ready for a pedal project. From there, you can hone your skills on a simple kit, such as a buffer or basic fuzz.
...don’t start with anything too complex. Begin by tinning wires and seeing if you can make a tidy job of wiring an XLR or jack plug. If you can do that, you’re probably ready for a pedal project.
Some kit suppliers offer ready‑drilled boxes at a slightly higher cost, but drilling your own enclosures isn’t too hard. Generally, for the standard size die‑cast zinc‑alloy boxes, the ‘proper’ method is to use a bench drill press, but they’re pretty easy to drill with a handheld electric drill if you secure the box in a suitable vice or adjustable work bench. My approach is usually to mark out the hole positions in pencil (most kit builds tell you where to put the holes), then use a centre punch to make a small dent in the case in the centre of each marked hole, to help prevent the drill bit from wandering. If you start by putting a smaller drill bit through all the marked holes first, larger bits will be less liable to stray off course, and if you don’t have a bit that’s quite large enough, you can always use a round file to enlarge holes.
Inexperienced kit builders often worry about their ability to decipher resistor colour codes. Plenty of online charts explain how those coloured bands work, including the FuzzDog’s free General Building Guide PDF (http://pedalparts.co.uk/docs/GeneralBuildGuide.pdf). But even though I trained in electronics, I still find some resistors hard to read where the colours aren’t well‑defined, particularly the tiny eighth‑Watt resistors used in some kits. Their colour bands remain inscrutable even under a magnifying glass! So, I double check every resistor with my multimeter before inserting it into the PCB. It’s a small time investment that can save a lot of time unpicking problems later on.
If you’re more experienced in tinkering with electronics, you might be happy referring to online schematics and building your projects from scratch, using strip‑board such as Veroboard, but buying the correct PCB makes for a tidier and more compact job, as well as being easier. You can usually track down the necessary components online, but note that buying these singly is much more costly than buying in bulk. If you plan on several builds, then it’s at least worth investing in a pack of resistors that cover all the key values.
I suspect, though, that for their first build most would rather buy a full kit of parts, complete with circuit board and assembly instructions. There’s also a safety net here, in that some DIY pedal companies (including FuzzDog here in the UK) offer a fault‑finding service should you really come unstuck. There are lots of companies around the world who offer such kits, and personally, I’ve bought them from FuzzDog and JedsPeds. These UK‑based companies offer kit options ranging from the bare PCB up to a full kit with a drilled enclosure, and can even build kits for you at a price (but where’s the fun in that?!). I’ve built compressors, modulation pedals and distortion and fuzzboxes, and they’ve all worked well.
Orientation
The build I’m using to illustrate this article is FuzzDog’s The Moon Phase phaser, which they rate as ‘intermediate’ in difficulty. It uses the aforementioned tiny eighth‑Watt resistors, but unlike some phasers that require matched FETs, this one uses LM13700 transconductance amplifier chips, so there’s no bias twiddling involved. As well as providing a number of kit options, Fuzzdog offer a small, optional daughterboard PCB that works for the majority of their builds and simplifies assembly. This fits on the back of the footswitch and can be cabled to the main board using a short length of ribbon cable (or separate wires). It also holds the status LED and terminations for the in and out jack leads and power connector, and helps keep the wiring inside the box nice and tidy. So if buying from them, I’d recommend choosing a kit option that includes it.
Setting up a clear workspace is essential, and having a few small containers on hand to hold the parts will help you keep things organised. It helps to sort out the resistors, capacitors and semiconductor devices into separate containers before you start. If you can fix up a way to hold your board secure while working on it, that can help too — you can buy some pretty sophisticated clamps, but for most pedal builds a couple of crocodile clips nailed to a block of wood works well enough!
When you unpack the full kit, you’ll find a bag with all the components plus the necessary PCBs, pots, switches and connectors. Battery clips are normally provided for pedals that can accommodate a battery, but if you always use a pedalboard PSU, you needn’t fit it. If you do plan to use a battery, check that your placement of switches and sockets still leaves room for the battery, and try to leave space for a piece of foam too — this can prevent the battery coming into contact with the circuitry.
Like many kits, this one has component numbers printed on the PCB, and a set of downloadable instructions tells you which values correspond to which part number. You can freely download the circuit diagram for any pedal FuzzDog offer, so you can easily check the complexity before you buy.
As long as you double check every component value and part number before fitting it, you really shouldn’t run into trouble.
While resistors and small‑value non‑electrolytic capacitors can work placed either way around, electrolytic capacitors, diodes and many other components have to be oriented correctly. If a component has one leg longer than the other, the positive leg will be the longer one. Printing on the board indicates which end the ‘stripe’ on a diode should be, and which way around electrolytic capacitors should be mounted — their negative side is generally denoted by a minus sign on the capacitor body. Kits usually include sockets for the ICs (I’d recommend using these rather than soldering chips directly to the board, as changing a defective or blown chip that’s been soldered to the board is a bit of a nightmare); both chips and sockets will have a small recess moulded at one end. Orientation is indicated both on the PCB and in a photograph, but if in doubt, there are also clear photos of a finished board. As long as you double check every component value and part number before fitting it, you really shouldn’t run into trouble.
It’s usually easiest to place and solder the resistors first. While it can take time, it’s a good idea to check them with a multimeter before fitting.
On With The Build
I fit the resistors first, checking each one using the meter (set to measure resistance), to make sure the right resistors go into the correct places. Take extra care when measuring high‑value resistors, because the resistance of your fingers can make the value look lower than it really is if you’re touching both ends. Next, place the capacitors and, finally, any diodes, transistors, FETs and IC sockets.
The resistors in this kit are the small eighth‑Watt types, but you could buy the larger standard quarter‑Watt resistors and mount these vertically on this PCB if you prefer. Something to watch out for with this kit is that a small number of resistors must be wired on the rear side of the PCB before fitting the IC sockets, as their soldered joints end up beneath those sockets. These are clearly marked in the instructions and in the on‑board printing, but it’s well worth checking for such things before you dive in.
If your kit uses transistors, you can allow these to stand slightly proud of the board, as long as they don’t protrude any further than the vertical electrolytic capacitors. Otherwise, they might foul the case lid that forms the base of the pedal. Crocodile clips or small pliers can be used as heat sinks on transistor legs and on diodes, though if you have a decent soldering iron and can make a good joint quickly, they are not always necessary.
When wiring the power connector, it’s vitally important that you don’t get the wires reversed. If you do, you could kill the transistors and chips, unless there’s a protection diode in the circuit (sensibly, in the Moon Phase kit there is). Most pedals use a ‘pin negative’ wiring scheme, so if you aren’t sure which tag goes to the centre pin of the power connector, check it with your meter. If you have one of the less common ‘centre positive kits’, that information will be included. If you plan to mix centre‑negative and centre‑positive pedals on the same pedalboard supply, you’ll need a supply with fully isolated outputs and ‘polarity swap’ power cables to feed your centre‑positive pedals.
For the flexible wires that are supplied with the kit, it pays to strip the ends, twist the individual strands and then tin the twisted end with some fresh solder. This will make it behave like a single piece of wire, which is easier to work with. And if you trim this tinned end at an angle, the wire is less likely to put up a fight when you try to poke it through a hole in the PCB or socket tag. When attaching wires to jack sockets or pots you can treat the ends in the same way, but I like to leave enough tinned wire exposed so that I can poke it through the hole in the tag and then wrap it around the tag with a small pair of pliers before soldering it. This habit, formed long ago during my ‘ministry’ electronics apprenticeship, keeps the wire in position as you solder it, which is not always so easy if you just poke the wire through the hole and hope it stays put while you solder. It also ensures that there’s no protruding end to short out on something.
The assembled electronics inside the supplied enclosure.If the hole in a component tag is too small for the wire, tin both the wire end and the tag, then lay the solder alongside the tag, and heat while applying just a little fresh solder until you see a smooth joint. It can be tempting to blow on a soldered joint to cool it but you really shouldn’t, as it may crystallise — either let it cool naturally, or use your pliers as a heat sink.
Sometimes, you’ll find that pots need to be mounted directly on the circuit board. In such cases, it’s important that you place an insulator between the back of the pot and the PCB, as this will prevent any short circuits. A thin piece of plastic rescued from a blister pack or even a couple of layers of duct tape will usually be enough to do the trick.
Other pots and switches need to be mounted on the case. If you’ve already drilled your case and the pots solder directly to the circuit board, a useful tip is to secure the pots and switches by just a single soldered lug, then do up the nuts finger tight. Once properly positioned in the case, you can then solder the other lugs knowing that they’re in the right position, and that you aren’t applying undue mechanical stress. As I mentioned, you have the option of enlarging the holes slightly with a round file. The washers provided with pots and switches should cover any unsightly gaps.
When you come to mount the finished circuit board in the case, adjust the nuts around the pots, switches and footswitch, so that these components don’t stick out too far. But at the same time, make sure that they’re not at the other extreme, where you can’t get the back of the case on!
Problems & Testing
Common problems for novice builders include accidental solder bridges between lands or tracks on the PCB, and dry joints. If you manage to get solder where it shouldn’t be, you can first try heating the offending blob, then tapping the board sharply on your work surface to see if that dislodges it. If that doesn’t work, try the solder sucker. An alternative is to buy solder wick, which is a bit like coax braid — this draws up unwanted molten solder by capillary action, rather than suction.
Dry joints are another common issue. These occur when solder fails to bond with one or both of the surfaces to be joined. But as long as you keep your soldering iron tip clean by wiping it on the damp sponge that comes with it, you should be able to make clean joints — as I said, just remember to heat the joint first and then feed the solder onto the joint. If the solder flows around the protruding component lead, bonding to it, and then flows outwards to form a smooth mound on the PCB land around it, the chances are that you have made a good joint. My preference is to trim the component leads after bending them just enough to stop the component falling out of the board when inverted, but before soldering. You can then solder them without excess wire getting in your way. This also means ‘stray ends’ can’t short out to nearby joints.
If the solder flows around the protruding component lead, bonding to it, and then flows outwards to form a smooth mound on the PCB land around it, the chances are that you have made a good joint.
It’s recommended to test pedal projects before fitting them in the case, and you can usually do this without worrying about having to resolder any wires as, invariably, the pots, switches and sockets (other than the power connector) fit into the case from the inside. Ideally, you’d test the board before wiring it to the footswitch too, and if you plan on making more than one pedal, something like FuzzDog’s Simple Tester kit can be invaluable. This houses a footswitch, jack sockets, power connector and terminals for wiring to the main board, allowing you to check the board is working properly before you commit to wiring it up to its own footswitch and jacks. Only four connecting wires are required between main PCB and tester. If you run into problems once the footswitch is connected, you know your switch wiring is the cause.
If there’s no signal through the effect when turned on (and any volume pot in the pedal is turned up!), start by checking that power is getting to the board. If the power is OK, use a magnifying glass to examine the solder side of the PCB very carefully, checking for dry joints or solder bridges. Also, confirm that ICs and transistors have been placed the right way round.
The finished article — while you can go to town with decoration, a label maker and a Sharpie pen can do what’s needed!If you do get sound but the effect sounds wrong, check that you have put the right resistors and capacitors in the right places, and that any electrolytic capacitors have been installed the correct way around. If you use a wrong value somewhere, you might still get sound but it may be distorted, faint or just plain wrong. In my experience, a careful visual examination usually reveals any problem, as component failures are fairly rare (unless you really overcook semiconductors when soldering them in place). That said, if you’ve had to unsolder a wrongly placed component, it’s just possible that you’ve damaged a track on the PCB, as they’re very narrow. If so, you should just replace that damaged section with a physical wire.
If the pedal works OK until you screw on the case lid (ie. the base for your pedal), the chances are that something is shorting out on the lid. I always line the inside of my lids with a piece of duct tape to prevent that problem, but you also need to do a visual check to ensure no components are protruding that might foul the lid. Once everything is working, you just have to decide on how to label the controls: a simple Sharpie or label printer does the job, but you can create your own custom style using waterslide decal paper transfers or paint if you wish.
Looking Back
So how was my Moon Phase kit to put together? While my build wasn’t without a few head‑scratching moments, none of that could be blamed on the documentation, which is creditably clear. Fitting all those small resistors took quite a long time because I checked each value with my meter, fitted the resistor, trimmed the leads and then soldered it in place before moving on to the next one. But it might have taken longer had I rushed it!
I found the desk magnifier pretty much essential for this build, and the Simple Tester kit gave me an easy way to check the pedal was working before connecting the footswitch. You could manage without that, but that would mean soldering sockets to wires and reconnecting them once you’d fitted the switch. If you plan to build more than one pedal it’d be a worthwhile investment. Based on this experience, I’d suggest that beginners pick a kit with fewer components and perhaps larger resistors. But once you get the hang of soldering on small PCBs there’s really no pedal kit you can’t tackle.
Thanks to FuzzDog for providing the kit used to illustrate this article.
FuzzDog: shop.pedalparts.co.uk
JedsPeds: www.jedspeds.co.uk