Erica Synths SWAMP - DIY Build

The Erica Synths SWAMP is a random CV and audio generator inspired by the famous Wiard Wogglebug module; it’s often the heart of self-generating patches and brings controllable randomness to any modular system.

Synthrotek did the world of DIY builders a solid by putting together these hard to find discontinued kits, and we have been wanting to get our hands on the SWAMP for a long time…and now you can too!

Purchase Quick Links: 

Erica Synths SWAMP – DIY KIT

Erica Synths SWAMP – Fully Assembled

Erica Synths SWAMP – Panel/PCB/IC

Before hoping straight into the build, let’s take a step back and highlight what separates this module from the original Wobblebug. 

The Erica Synths SWAMP module introduced numerous modifications and improvements to extend the potentiometer range. It added an audio input, which, when connected, replaced the internal Tone oscillator, and the expensive dual vactrol.

The S&H (sample and hold) circuit was build around the Riga S&H IC (AS1100CK2) and ES added audio waveform selection switches, CV output configuration jumpers and much more. All of these are reasons to have just one in your rack!

To sum everything up, the Erica Synths SWAMP is an advanced multi-level kit that can pose a few challenges for even the experienced builder. Packed and distributed by Synthrotek, the entire DIY line of modules is now available for you to take on! (so we had to)

Before you build ...

When you open the SWAMP kit, it can easily be intimidating. It contains a lot of parts and multiple PCBs. Make sure to open the kit in an enclosed area too as it is easy to lose a piece or two. The nice thing about Synthrotek kits is that, 9 times out of 10, their kit components are packed in line on a roll of masking tape. This just keeps everything all together. Upon opening up our kit, we noticed a few resistors and diodes had shifted in the packing/shipping process so we took caution before jumping right in. 

Erica Synths SWAMP - Time Lapse Build

Play Video

Synthrotek provides a great visual BOM with their kits, but sometimes the colors are hard to match up on the printed version. We like to use the online visual BOM as a reference and use our component tester to test any parts we have in question. Before jumping into the build, try to get an idea of the layout of the board due to the tight component placement. Here is where the novice builder or experienced builder can feel intimidated. Take a big deep breath; we have you covered since you only have a visual BOM. 


Even though these kits have been discontinued by Erica Synths, you can find some assembly instructions to the kit online…. if you go digging…. We decided to make it easy on you and post them below.

Visual BOM:

Erica Synths Kit Assembly Guides:

SWAMP Documentation and Assembly:

On with the build:

There are a lot of parts in this kit, but realistically you can just look at the PCBs as multiple module builds. Pick your board (either the main or the control) and separate the parts and PCB accordingly. We started with the main/logic board since it has the most resistors and will take longer to place/tack everything down. Starting with the diodes and resistors, place the components in their rightful places making sure to match the polarity of the diodes. Resistors are both 1% and 5%. Make sure you place the correct ones where they go. Top down soldering is our preferred method of soldering but we always double check the backside of the PCB in case we need to touch up anything along the way. 

Erica Synths SWAMP Build Gallery

ICs and Caps

As with other builds, start with the ceramic/film caps first and then move onto the electrolytic caps. The electro caps have polarity (long leg/short legs). Make sure you place the long leg (+) into the square hole on the PCB silkscreen/pad. If there is not polarity on the cap, just follow this same rule. 

Sockets are next. IC sockets are a weird part to place because normally by the time you get to place them, the PCB will not lay flat. An easy way to get past this is to place a dab of solder on the pad and then line up the socket to the pads on the appropriate side. Heat the bottom (opposite side of the socket top) and gently press on the socket. You will hear a click and the socket will set itself into place. Turn the board over and tack the rest of the socket pins down and you are good to go. This method is also great for power headers so feel free to place that piece at this point in the build as well. 

Finishing things up… (you're half way there)

As you approach the last of your soldering on the logic board, make sure you double check your joints. (not the kind you smoke). You want to make sure you had good solder flow throughout the build so that nothing shorts when you power it on. Once you have done this and completed the Erica Synths SWAMP logic board, set it aside, rinse and repeat with the control board. 

Features and Specifications


  • Three random audio frequency outputs
  • External audio input routed to ring modulator
  • Three random CV outputs
  • Clock input and output to sync the module to your modular system
  • CV control over internal clock for even more extreme randomness
  • Skiff-friendly design


  • CV Level: 0-10V or -5V – +5V
  • Audio Output Amplitude •10Vptp
  • Width: 14HP
  • Depth: 35mm
  • Current draw:
    • +12V: 60mA (max)
    • -12V: 39mA

The Control Board

This board has less resistors (34 vs the logic board 54), contains LEDs, two switches, three vactrols and different values of potentiometers. These are all parts to be aware of as your build nears completion. Following the footsteps of the logic board, work your way through the resistors, diodes, caps and IC sockets. You do have 2 fuses and a couple ferrite beads that also have to be tacked down so be aware of that. 

As you approach the end of the build, do not tack down the LEDs (mind their polarity too) or the jacks or pots before placing the panel on the module. Once everything lines up, use the nuts to hold the panel in place so you can flip the board over and solder everything down. 

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Erica Synths SWAMP - Purchasing Options

Synthrotek offers a several options when it comes to purchasing the Erica Synths SWAMP. Their prices are excellent and the quality of this build is way worth it! If you are interested in buying the kit, the assembled module or just the PCB/Panel/IC, click on the images below and you will be redirected to their site to purchase! Make sure and tell the gang at SR that we sent you!

Erica Synths DIY System Demo

Completing the build

The Erica Synths SWAMP module has both header pins as well as a standoff to help bring the boards together. Make sure you place any ICs if you haven’t already and gently push the two boards together. They will fit snug but they should not be forced. If any of the pins or headers to not match up, desolder that part and line things up accordingly. 

When you have the boards together, place the power cable into the header and attach it to your case or rack. We always use our Synthrotek TST module to test things prior to placing any new builds into our racks. This ensures that nothing is going to short and we can protect our expensive investment. 

Our Final Thoughts . . .

SWAMP is an interesting module to say the least and we have yet to scratch the surface of it. The build was a long build that took patience and attentiveness due to the close proximity of the parts and multiple boards. As long as you take on one board at a time and you do not rush through the soldering, any builder can complete this build. With the added features to the SWAMP module, it was a no brain purchase over the Wogglebug. 

The matte black panel and the two yellow LEDs also give the module a little character when racked. In the end, the Erica Synths SWAMP module is an excellent module to give some much needed flavor to your patches. Head on over to Synthrotek and pick up a kit before they are gone… oh and tell the gang over there we sent ya!

Comments or Suggestions?

If you have questions about the build process or suggestions/feedback about this article, feel free to let us know by contacting us  We look forward to hearing from you!

Until the next build … 

~ f i N

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