MOD Kits DIY Wahtz Wah

DIY-built Wah Pedal Kit

Ever thought about building your own pedals? Getting started  can be a bit overwhelming, so rather than trying to first learn enough to design and build pedals from scratch, many players instead opt for starting with a pre-packaged kit. These are not only already designed and proven circuits, but usually include all the components needed to assemble the pedal - just add tools and labor. One company that offers a wide selection of different effects pedal kits, and even amplifier kits for more experienced builders, is MOD Kits DIY. Let's look at  their Wahtz Wah wah pedal kit - it's not too difficult to build, and can be completed successfully by anyone with basic soldering skills who can take their time and follow directions.  

What You Need To Know

• Unlike some kits from some companies which clone the circuits of well-known pedals, the MOD Kit DIY circuits are not clones, but their own original designs. All of their kits use point-to-point wiring.

   

• The kit is shipped to you well-packed in a cardboard box, with all the instructions and parts for the actual kit contained in clear plastic bags. All of the mechanical and electronic components necessary to build the complete wah are included - unlike PCB-only DIY projects, there's no need to source your own parts.

• While all the parts are included, you'll need to provide the tools: soldering station, solder, desoldering tool, wire strippers and cutters, pliers, a Phillips screwdriver, pin punch, and a small crescent wrench. While not absolutely essential, a digital multimeter helps for testing and troubleshooting. You'll also need a bit of Vaseline to lubricate the wah's gears, and some contact cement to glue the treadle's rubber top surface and bumpers in place. The instructions, which are included with the kit and are also available to view online as a PDF file, provide a complete tool list.  

   

• While this kit is really better for someone's second or third build instead of their first one, basic soldering instructions and tips are also included in the instructions for beginners. I'd recommend having some practice and experience under your belt, and maybe trying your hand at a couple of easier pedal builds before taking this one on.

   

• The very first step in the build (and one that goes unmentioned in the instructions) is painting the case - painting the completed pedal and achieving half-way decent cosmetic results would be very difficult.  Since this usually takes a few days, don't plan on having the entire pedal finished the day the kit arrives (unless you don't mind a bare metal case). I used two different paint colors - one for the treadle and one for the main case. I let myself get into too much of a hurry and didn't read the paint instructions, so when I sprayed the clear coats on too early, the paint started lifting and I had to strip it all off and start over. If there's one thing you need when doing projects like this, it's patience. Get into a rush, and it usually costs you time instead of saving it.

   

• After finishing the color coats, I applied water slide decals to the case to label the I/O and power jacks, then covered it with clear to help prevent the labels from wearing off.

   

  

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• While perfectly usable multi-strand wire is included with the kit, I instead decided to use solid core wire from my own stash. This can be bent to shape and allows a cleaner and more deliberate wire routing.

   

  

• After completing the wiring, it's time to install the electronic components. Outside of the painting, you can complete the entire assembly process in an evening if you're fairly proficient at soldering. Count on it taking extra time if you don't have resistor color codes memorized and have to look them up for each part. Here's a tip - if you don't know how to read the codes, use the multimeter to tell you the value of the resistor - that way, you don't have to memorize anything. 

• MOD Kits DIY rates the difficulty of each of their pedal kits, which helps builders avoid pedals that may be beyond their experience and building skill level. On their 1-5 scale the Wahtz Wah is rated a 4. At first glance at the relatively low parts count I thought that might be a bit high on the scale, but as I worked through the build, I understood where things could possibly get a bit tricky for those who are not used to working methodically and checking their work as they go along. I don't say that to scare you - if you can solder decently, you can build this kit - but I do want to emphasize the importance of working carefully. A little extra time spent during the build means less (or no) time spent troubleshooting problems later.

   

• The included components are of good quality, with a DPDT switch for true-bypass switching and a high-quality, long-life pot designed specifically for wah use. The inductor included is a black Dunlop model. Of course, the point-to-point design of the pedal and DIY nature of the product make it easy to substitute a different inductor if you prefer. The pedal can be powered by a 9V battery or an external 9V DC power supply (not included), and the power jack uses the industry-standard 2.1mm center negative-plug type.

   

• The first time I plugged it in, it worked. Again, I can't emphasize the importance of working slowly and methodically and double-checking everything as you go along. If you have a problem, MOD Kits DIY really helps by providing test points in the circuit and their approximate voltages - by measuring with your multimeter, you can quickly track down and correct any issues.

   

• The MOD Kits DIY website describes the Wahtz Wah sound very accurately as producing the "classic wah tone you've come to expect, with a hint of extra bite and growl." In fact, when kicked in, I measured about a 6 dB increase in level over unity gain, and the overall tone, while similar to my GCB95 Crybaby, is a bit brighter and more cutting.

   

• There is also a bit more distortion to the sound (and some corresponding noise) compared to some other wahs; if you're looking for an exceptionally clean sounding wah, the Wahtz Wah might not be your best choice, but I do like the pedal's slightly grittier sound overall. There's plenty of sweep, and you can adjust the filter sweep range by how you set the pot relative to the rack gear.

   

Limitations

• While instructions and diagrams are included for adding an LED indicator, and the wah case itself is even drilled for one, the parts for adding a LED to your pedal are not included with the kit.

   

• While they're available to view or download online, the test points and voltages are not included in the manual.

• Assembly instructions on the order of some steps could be improved on. For example, I found it easier to insert and tighten the wah pot without the footswitch installed, which you're instructed to install first.

   

• The Wahtz Wah's point-to-point design allows for relatively easy experimentation and modification, but no mod tips or suggestions are offered in the manual beyond the instructions for the optional LED on/off indicator.

• The leads of the battery clip were too short to reach from where they needed to go to the battery compartment. I had to extend them with a couple of pieces of wire, and covered the extension points with heat shrink tubing.

Conclusions

This was a fun and enjoyable project that resulted in a very usable pedal. The only real frustrations were largely the result of my own doing and because I got into too much of a rush.

If your main reason for wanting to build this pedal is to save money, then you might want to reconsider. You can buy a new, pre-built wah for about the same price or even a little less than the price of the Wahtz Wah kit, and the price of the build will be even greater once you factor in the cost of paint, labels, and tools. Still, those tools will be useful for other projects, and you probably already have most of what you'll need anyway. If you're looking for a foundation for your own mods, this pedal is an excellent choice due to the point-to-point layout. But even without any mods, the Wahtz Wah is a cool-sounding pedal with its own appealing take on the classic wah sound.

There's a lot of satisfaction to be had in a job well done, and those who enjoy building pedal kits will dig the Wahtz Wah from MOD Kits DIY. This is the first kit of theirs that I've built, but it won't be my last. If you're looking for a fun project and cool new addition to your pedalboard, definitely check out their kits - and when your friends ask where you got the new pedal, you can tell them you built it yourself.

Resources

MOD Kits DIY "The Wahtz Wah" Pedal Kit ($109.95 "street", available from Amplified Parts)

MOD Kits DIY's product web page

Sound examples

Instructions (PDF file)

Troubleshooting guide (PDF file)

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Phil O'Keefe is a multi-instrumentalist, recording engineer / producer and the Senior Editor of Harmony Central. He has engineered, produced and performed on countless recording sessions in a diverse range of styles, with artists such as Alien Ant Farm, Jules Day, Voodoo Glow Skulls, John McGill, Michael Knott and Alexa's Wish. He is a former featured monthly columnist for EQ magazine, and his articles and product reviews have also appeared in Keyboard, Electronic Musician and Guitar Player magazines.