General Guitar Gadgets (GGG) is a small family business near Good Hope, Missouri. JD Sleep started the site in 1998 to share printed circuit board layouts for guitar effects, and it has been a full-time business since 2006. Today the site has free do-it-yourself stompbox projects, and the store sells complete kits and ready-to-solder circuit boards for many of them. You can read more on the About page.

Yes. Every project on The Projects page is free to use, whether or not you buy anything from us. That includes the schematic, the parts layout and wiring diagram, the bill of materials, the build instructions and, for builders who etch their own boards, a ready-for-transfer circuit board layout.

Each project page has the files you need to build that effect:

• Schematic – the circuit diagram.
• Parts layout and wiring diagram – where every part goes on the board, and how the board connects to the jacks, pots and switches.
• Bill of materials – the parts list.
• Build instructions – how to put that project together.
• Modifications – on many projects, options for changing the sound.
• Ready-for-transfer board layout – only needed if you etch your own circuit board.

Read the project files together with our General Build Instructions.

They are replicas of the original circuits, tuned by ear, and they sound great. Where an original part is no longer made, or is hard to find or very expensive, we use a modern part that sounds as good or better. We also use true bypass switching with an LED indicator on every kit that has bypass switching, even when the original pedal did not.

The names of the original pedals are trademarks of their owners. General Guitar Gadgets is not affiliated with those companies.

Our kits and circuit boards are sold for you to build yourself. JD does occasionally offer finished stompboxes for sale; when he does, you will find them in our Reverb shop.

Yes, many people do!

To give you as much flexibility as possible. Because the pots, jacks and switches connect with hookup wire, you can use the enclosure and the layout you want. The extra pads on many boards are there for modifications and for different versions of the same circuit. Our boards are also laid out so they can be etched at home, which is why they are not as small as they could be.

Email us at [email protected]. Our goal is to answer within two days, so please check your spam folder if you have not seen a reply. We are a small family business and the shop has no phone, so we do not have a business phone number. See the Contact Us page for more.

We love suggestions. Email [email protected] with the pedal you have in mind.

A complete kit has the parts and materials you need to build the project: the ready-to-solder circuit board, the parts that go on the board, the potentiometers, the footswitch and LED, the input, output and DC power jacks, a battery snap, hookup wire, lead-free solder, standoffs for mounting the board and, if you choose one, a pre-drilled enclosure. The exact contents are on the kit's page in the store and in the project's bill of materials.

We use the best parts we can within the price of the kit:

• Double-sided circuit boards with plated-through holes on every pad, which stand up to rework.
• 1% metal film resistors, except for the few values that are not made in that type.
• High-quality capacitors, mostly Panasonic™ where available.
• Switchcraft™ input and output jacks.
• Mill-Max™ sockets for ICs and for specialty transistors.
• A solid plastic battery snap, not a vinyl one.
• RoHS-compliant parts, including the lead-free solder.

There is more on the store's Kit Information page.

A 9-volt battery, a power adapter and tools are not included. Paint and labels for the enclosure are up to you. Kits for circuits that originally used germanium transistors come with a good set of silicon transistors and a transistor socket instead (see the next question).

No. Good germanium transistors have to be selected one at a time, and if you want them you can probably find a better set than we could supply. Every kit for a circuit that originally used germanium transistors comes with a good quality transistor socket, a good set of silicon transistors, and instructions for building a great sounding fuzz or booster with them. Because the transistors sit in sockets, you can try germanium ones later without any desoldering.

Most kits offer these choices:

• 125B – the standard size. The wiring diagrams on the site are drawn for this enclosure and the 1590BB.
• 1590BB – the larger box. It is wider but shallower than the 125B, so the jacks are a tighter fit. See Building a Kit in a 1590BB Enclosure.
• 1590B – the smaller box, about the size of the small MXR™ pedals. It is a tighter build: the jacks go on the sides and the board sits over the backs of the pots. See Building a Kit in a 1590B Enclosure. On some kits not every option fits in this box.
• No enclosure – at a lower price, if you already have a box or want to drill your own.

If this is your first build, the 125B is the easiest to work in.

Kit enclosures come pre-drilled for that kit. If you want to paint or label yours, see “How do I paint and label my enclosure?” below.

Yes. Ready-to-solder circuit boards are sold separately for many projects in the store. You then buy the rest of the parts yourself using the project's bill of materials.

Often, yes. We keep a large stock of capacitors, diodes, ICs, sockets and potentiometers. See Other Parts We Carry, and email us at [email protected] if you see something you need.

No. Kits and circuit boards are available for many of the projects, but not all of them. When a project has a kit or a board, its project page has a link to buy it. The projects without a kit still have all their files, so you can build them from your own parts.

Pick a circuit with few parts. Simple boosters and fuzzes, such as the EHX™ LPB2™ replica or a Fuzz Face™ replica, have a small board and little wiring. Overdrives such as the Ibanez™ Tube Screamer™ replica are a good next step. Leave phasers, delays and other projects with many parts until you have a build or two behind you.

Yes, and we encourage it. Many project pages have a Modifications file with tested changes, and many of our boards have room for them. Some kits also have an optional pack of parts for popular modifications.

Often. ICs and specialty transistors sit in sockets in our kits so you can try alternatives. For example, the Tube Screamer™ mod pack adds LF353 and RC4558 op amps to compare with the stock JRC4558D. Make sure the replacement has the same pinout; transistor pinouts in particular differ between part numbers.

We like great sound more than vintage part numbers. Every kit is tuned by ear with quality modern parts, and we only change a part from the original when the result sounds as good or better.

All orders go through our online store at store.generalguitargadgets.com. Project pages on this site link straight to the kit and circuit board for that project.

We usually ship within 1–2 business days. Around postal and public holidays it can take a day longer. Orders go out by USPS, UPS, FedEx or DHL, and the delivery time depends on the carrier's service to your area.

Yes. Shipping cost and delivery time are shown at checkout. Your country may charge import duties or taxes when the package arrives; those are not part of our prices or shipping charges.

We often have a free shipping offer for larger orders. The current offer and its code are in the banner at the top of this site.

You may return anything you buy from us for any reason, as long as it is in new, unused condition. For a kit, that means complete and unsoldered. You pay the cost of shipping it back, and the original shipping charge is not refunded. The full policy is on the store's refund policy page.

The payment methods available to you are shown at checkout in our store.

Check the kit against the project's bill of materials before you start soldering. We make every effort to send a complete and correct set of parts, but mistakes do happen. Some parts also look different from the photos in the instructions; see Identifying Capacitors. If something is missing or wrong, email us at [email protected] with your order number and the part, and we will help.

We moved to a new store on June 29, 2020, and accounts from the old store were not carried over. You can create a new account in the current store.

Yes. JD has built well over a thousand working stompboxes and has complete confidence in your ability to build one too. Before you start, spend some time with the links on our beginner information page. Then choose a simple first project, read all of its files, and take your time.

Yes, building a kit means soldering. It is not hard to learn. If you have never soldered, practice first on some scrap wire or an old circuit board. A good joint is shiny and cone-shaped, and covers the pad and the lead. Poor solder joints are one of the most common reasons a new build does not work.

This is what we keep on the bench when we assemble a board:

• Soldering iron and stand, and solder
• Small side cutters
• Wire strippers
• Small needle-nose pliers
• A multimeter
• A bright desk lamp and a small magnifying glass
• Small and regular screwdrivers, and a wrench or pliers for the nuts on the jacks, pots and footswitch
• A desoldering tool for fixing mistakes

JD wrote about the tools he uses in two blog posts: Hand Tools and Desolder Tools.

Kits include lead-free solder, but many builders like to keep their own favorite solder on hand.

Use a pencil-type iron made for electronics, with a small tip. A temperature-controlled iron is the easiest to work with. Do not use a soldering gun or a large iron meant for plumbing or sheet metal. Use thin rosin-core solder made for electronics, and never acid-core plumbing solder, which will ruin the board. Lead-free solder needs a little more heat than leaded solder.

No. You can build a kit from the parts layout, the wiring diagram and the instructions. It does help if you can follow the schematic through the layout, especially if something does not work. Our Introduction to Electronic Parts shows what each part looks like in real life and on a schematic.

1. Read our General Build Instructions and the pages under Building Kits.
2. Download and print all the files for your project. A color printout is best.
3. Check that all the parts in your kit are there and correct.
4. Plan how everything will sit in the enclosure you chose.

Then build in this order: solder the parts to the board, finish the enclosure if you want to, mount the board and the other parts in the enclosure, and wire them together.

It depends on the project and on your experience. Plan on an evening or two for a simple first kit, and longer for projects with many parts. Do not rush: most problems come from hurrying.

Wear eye protection when you clip leads and when you drill. Solder in a room with good ventilation, keep the hot iron in its stand, and wash your hands when you are done. If you drill your own enclosure, clamp it down first; see Drilling Enclosures.

Solder them in this order:

1. Sockets, if used
2. Resistors
3. Capacitors
4. Diodes and transistors
5. Integrated circuits (ICs)

When you are done, look over every joint under a bright light, through a magnifying glass if you can.

Resistors are marked with colored bands. Read the bands and match the value to the project's bill of materials, or measure each resistor with a multimeter before you solder it in. Measuring is the safest way, because some band colors are easy to confuse. The resistor guide in our Introduction to Electronic Parts explains the color code.

Capacitor markings are not standard, and the capacitors in your kit may not look like the ones in older photos. For example, a 0.001uF capacitor may be marked 1nK100, a 0.1uF capacitor u1K63, and a 1uF capacitor 1uK63. See Identifying Capacitors for photos.

Film capacitors often use a three-digit code in picofarads: the first two digits, then the number of zeros, so 103 is 10,000pF (10nF, or 0.01uF). A letter after it is the tolerance: J is 5%, K is 10%. 1000pF = 1nF = 0.001uF.

• Electrolytic capacitors – the stripe on the body marks the negative lead; the longer lead is positive.
• Diodes – the band on the body must match the band on the parts layout.
• LEDs – the longer lead is positive.
• Transistors – match the flat side to the outline on the parts layout.
• ICs – match the notch or dot at one end to the layout.

Resistors and small film or ceramic capacitors can go in either way round. Always check the parts layout for your project.

Yes. Transistors, diodes, LEDs and ICs can be damaged by too much heat. Heat each joint only long enough for the solder to flow, usually a few seconds, and let the part cool before you solder its next lead. Our kits include sockets for ICs and for specialty transistors: solder the empty socket to the board, then plug the part in when all the soldering is done. Make sure everything that goes in a socket is plugged in before you power the pedal up.

Use a spring-loaded desoldering tool (a “solder sucker”) to remove the solder, then lift the part out. Our circuit boards are double-sided with plated-through holes and can usually take several reworks with almost no damage. JD describes the tool he uses in Desolder Tools.

This order leaves the most room for your soldering iron:

1. Mount the potentiometers.
2. Mount the DC jack.
3. Mount the finished circuit board on its self-stick standoffs.
4. Wire and solder the connections to the pots, the DC jack and the switches.
5. Mount the input and output jacks, then wire and solder them.
6. Solder in the battery snap.

Before you solder any wires, check that the board and all the parts fit where you plan to put them.

Break it off. We do not use that tab, and most commercial stompboxes do not either. Grip it with needle-nose pliers or side cutters and bend it to the side; it snaps off easily. The pot will then sit flush against the inside of the enclosure.

Keep the footswitch as low as you can: turn the lower nut up the threads until three or four threads show below it. The lock washer goes inside the enclosure and the plastic washer outside. There are photos on the Installing the Footswitch page.

Our Wiring Input/Output Jacks page has photos of the jacks we use, with notes on what connects to each solder lug. Follow them together with the wiring diagram for your project.

We use 24 gauge stranded, insulated wire; 22 or 26 gauge also works. Pre-bonded stranded wire is an excellent choice, and it is what we put in the kits. Using several colors makes the wiring easier to trace. Avoid low-grade wire, and avoid solid-core wire unless you have experience with it.

All the grounds must be connected together. You can run a ground wire from each jack and pot back to the board, or link them one to the next and bring a single wire back to the board; either way works. We recommend that you do not rely on the metal enclosure to make ground connections. If a nut ever works loose, you can get a connection that cuts in and out, and that is no fun in the middle of a gig.

Yes. Keep the wiring neat and no longer than it needs to be, while leaving enough slack to lift the board for service. Run the input and output wires as far from each other as you can, and do not run wires across the top of the board. Good wire routing helps prevent hum, noise and squealing.

It is a good idea. Check the board, the wiring and the fit of the parts before you tighten everything down, then plug in and test. It is much easier to fix a problem while you can still reach both sides of the board.

The diagrams on the site show a kit in a 125B or 1590BB enclosure. In the smaller 1590B the jacks go on the sides and some boards sit differently, so look carefully and plan the wiring before you cut any wire. See Building a Kit in a 1590B Enclosure and Building a Kit in a 1590BB Enclosure.

Yes. Every kit can be ordered with no enclosure, and we have paper drilling templates on the Drill Your Own Enclosure page. The templates are a guideline only. Wear eye and hearing protection, and always clamp the enclosure down before you drill.

Print a template at 100% with “fit to page” turned off, and check it with a ruler before you drill. Center-punch each hole and start with a small pilot hole; a step drill bit gives clean holes in aluminum.

Here is the method from our General Build Instructions:

1. Sand the enclosure smooth, mostly with #220 paper, and wipe it down with naphtha.
2. Apply one coat of automotive gray primer, sand lightly with #300 paper, and wipe it down again.
3. Apply one coat of paint.
4. Add your labels.
5. Apply a clear coat to protect the labels.

For labels, builders use permanent marker, freehand paint, printed stick-on labels, iron-on transfers, or water-slide decals under a clear coat. Powder coating gives the toughest finish if you can get it done. The details are in the General Build Instructions.

Yes. Every project has a ready-for-transfer board layout, and our boards are designed so they can be etched at home. Making Your Own Printed Circuit Boards takes you through transferring the layout, etching and drilling. It is a messy, time-consuming job, so if you only want one board, a ready-to-solder board from the store is the easier way.

Most of our projects run on a 9-volt battery or a 9-volt DC adapter. The DC jack is wired the standard way for stompboxes: a 2.1mm barrel plug with the negative on the center pin. Use an adapter that is filtered and regulated. For how the power is wired inside the pedal, read Powering Projects.

No. A reversed or higher-voltage adapter can destroy ICs, transistors and electrolytic capacitors in seconds. Check the label: it should say 9V DC, with the center-negative symbol. Some commercial positive ground pedals use a positive-tip adapter; we don't recommend that wiring, because sooner or later that adapter gets plugged into a negative-tip pedal and damages it.

The input jack is the power switch. Plugging a cable into the input connects the battery, so the pedal is on for as long as a cable is plugged in, even when the effect is bypassed. Unplug the input cable when you are not using the pedal.

No. The DC jack has a switch built in. When an adapter is plugged in, the jack disconnects the battery and the pedal runs from the adapter.

Some older circuits that use PNP transistors, such as the Fuzz Face™, the Tone Bender™ and the Rangemaster™, have the positive side of the supply connected to ground. You cannot run a positive ground pedal and ordinary negative ground pedals from the same daisy-chained power supply; the shared ground connection shorts the supply, and it will not work. Use a battery, or a separate power supply, for the positive ground pedal.

Another answer is a charge pump, which lets a positive ground circuit run from a standard negative ground supply. See our Charge Pumps project.

Most often the adapter is the cause. Many inexpensive wall adapters are not well filtered or regulated, and they add hum and buzz to the signal. Try a battery: if the hum goes away, use a filtered, regulated supply made for effects pedals. Hum can also come from a ground loop elsewhere in your rig.

Only if the project's documents say that the circuit and its parts are rated for it. Our Charge Pumps project can produce higher voltages from a 9-volt supply for circuits that are designed for them, and there are other supplies on the Power Supplies page.

Yes. JD explains an easy way to do it, without disturbing the pedal's wiring, in Adding a Power Jack.

With true bypass, the footswitch takes the circuit completely out of the signal path when the effect is off, so your signal goes straight from the input jack to the output jack. All of our kits with bypass switching use true bypass, including replicas of pedals that did not have it originally.

It is a footswitch with three sets of contacts. Two sets switch the input and the output for true bypass, and the third turns the LED on and off. A DPDT switch has two sets of contacts, enough for true bypass without an LED. Wiring diagrams for both are on the Many Bypass Switching Options page.

The LED needs a current limiting resistor, shown as R1 in our switching diagrams. Its value is generally between 1k and 8.2k, and typically 4.7k; a higher value makes the LED dimmer. Many of our boards have this resistor built in, with a pad marked “L” for the wire to the LED.

A small pop is common with true bypass switching, and there is usually a simple cure. R.G. Keen explains the causes and the fixes in an article linked from our Bypass Switching Links page. The usual cure is a pull-down resistor of around 1M to 2.2M from the circuit's input, and its output, to ground.

Yes. Any stompbox can be buffered if you want it to be, the way Boss™ and Ibanez™ pedals are. We have buffer projects under Boosters & Volume.

Yes. The Many Bypass Switching Options page has wiring diagrams for two effects in one enclosure, each with its own true bypass switch and LED.

Be patient and work through it step by step. A build that does not work almost always has a mistake in it, not a bad part. Check these first:

1. Power – a fresh battery, or the correct adapter, and 9 volts reaching the board.
2. Sockets – every IC and transistor plugged in, the right way round.
3. Part values and positions – compare each part with the parts layout and the bill of materials.
4. Orientation – electrolytic capacitors, diodes, transistors, ICs and the LED.
5. Solder joints – look for dull or incomplete joints, and for solder bridging two pads.
6. Wiring – follow every wire on the wiring diagram, especially at the footswitch and the jacks.
7. Shorts – nothing on the board or the back of the pots touching the enclosure.

The Guitar Effects Debug Page linked from our beginner information page is required reading.

A good joint is smooth and shiny and flows onto both the pad and the lead. A cold joint looks dull, grainy or balled up; reheat it with a little fresh solder. A solder bridge is a blob joining two pads that should not touch; remove it with a solder sucker. Don't hold the iron on a pad longer than you need to.

If nothing passes even in bypass, the problem is in the jacks or the footswitch wiring, not on the circuit board. Check your cables, the wires to the input and output jacks, the ground connection between the jacks, and the footswitch wiring.

The signal is being lost on the board or on its way there. Check that power reaches the board, that the ICs and transistors are in their sockets the right way round, that the board input and output wires go to the right lugs on the footswitch, and that the pots are wired correctly. Then trace the signal with an audio probe (see below).

The LED is most likely in backwards; turn it around. If that does not help, check the LED resistor, the wire from the board to the LED and the footswitch lugs that switch it. An LED can also be damaged by too much heat when soldering.

Look for a resistor or capacitor of the wrong value, a transistor in the wrong way round or in the wrong position, or a weak battery. If the project has a trimmer for setting the bias, adjust it as the build instructions describe. Fuzz circuits are especially sensitive to the transistors and their bias.

First try a fresh battery, to rule out the power supply. Then check that every ground is connected, keep the input and output wires short and apart, and test with the back plate on the enclosure, because the closed metal box shields the circuit. High gain pedals make some hiss at high settings; that is normal. A put-put “motorboating” sound usually points to the power supply or a bad filter capacitor.

Check that the adapter is 9 volts DC with the negative on the center pin of a 2.1mm plug, and check the wiring to the DC jack. If the pedal is a positive ground circuit, see the positive ground question under Powering your pedal.

Unplug it right away. Reverse polarity or too much voltage usually damages the polarity-sensitive parts first: look for bulging or leaking electrolytic capacitors, and suspect the ICs and transistors. Because our kits put ICs and specialty transistors in sockets, those can be swapped without desoldering.

It is a simple tool for following the signal through the circuit. It is a wire with a capacitor in line that feeds an amplifier. You play a signal into the pedal and touch the probe to points along the signal path on the schematic, starting at the input. The place where the sound stops or goes wrong is where the problem is. The Guitar Effects Debug Page linked from our beginner information page shows how to make and use one.

With the pedal powered and a cable in the input jack, put the black lead of your multimeter on ground and measure the DC voltage at the supply and at each pin of every transistor and IC. In a 9-volt circuit, the supply pin of an IC should read close to 9 volts, and the inputs and output of an op amp usually sit near half the supply, about 4.5 volts. Write the readings down; a pin that is far from what the schematic leads you to expect points to the problem.

Email us at [email protected]. Tell us which kit or project you built and what it does or does not do, and include clear, well-lit photos of both sides of the board and of the wiring, along with any voltages you measured. The DIY forums on our Links page are also full of experienced builders who are glad to help.

Returns are for kits that are complete and unsoldered, so a kit you have started to build cannot be returned for a refund. Do email us at [email protected], though. We want you to end up with a working pedal.

A printed circuit board: the board that the parts are soldered to. Copper traces on the board connect the parts.

A finished, professionally made circuit board that is ready for you to solder the parts to. Ours are double-sided with plated-through holes.

A mirror-image print of the copper side of the board, for builders who make their own circuit boards with an iron-on transfer. If you have a kit or a ready-to-solder board, you do not need it.

The parts list for a project. Use it to identify and check the parts in your kit.

A pot is a variable resistor: the part behind each knob. The letter is the taper, which is how the resistance changes as you turn it. B is linear, A is logarithmic (audio), and C is reverse logarithmic. So “100k B” is a 100k linear pot.

A small adjustable resistor on the circuit board that you set once with a screwdriver, for example to set the bias of a transistor.

They are the two types of bipolar transistor. Most modern circuits use NPN transistors and a negative ground. Many early fuzz and booster circuits used PNP germanium transistors and a positive ground.

They say which side of the power supply is connected to the circuit's ground. Nearly all pedals today are negative ground. Some older designs are positive ground and cannot share a daisy-chained power supply with negative ground pedals.

Germanium transistors were used in the fuzz and booster pedals of the 1960s. They vary a great deal from one to the next and change with temperature. Silicon transistors are consistent, quiet and easy to get.

An IC is an integrated circuit, a “chip”. An op amp is a type of IC used as an amplifier in many overdrives, distortions and other effects.

Diodes that cut off the peaks of the signal to create overdrive or distortion. Different diodes, and LEDs used as diodes, clip differently, which is why some kits have a switch to choose between them.

They describe switches. The first part is the number of poles, or separate sets of contacts: single (S), double (D) or three (3). “DT” means double throw: each pole switches between two positions.

A plug-in power adapter, the kind with the transformer built into the plug.

The way the wires are laid out inside the pedal, so they do not pick up or cause hum, noise or oscillation.

Standard sizes of die-cast aluminum enclosures. The 125B is the usual single pedal size, the 1590B is a little smaller, and the 1590BB is the larger, wider box.

Restriction of Hazardous Substances. RoHS-compliant parts and solder are made without lead and certain other hazardous materials.