Adventures in Photoetching - or - Making Old School PCBs for Fun

At the first of the year I published an article on two new versions of the EHX Big Muff Pi effects pedal I'd completed. One was built on a home-etched board a friend had sent me using a pattern from the Effects Layouts blog. At the time I mentioned that I had done photo-etching in the past starting when I was in graduate school (getting a Ph.D. in chemistry - so applying chemistry to something guitar pedals, electronics, and music is "really cool" in my book!). Since I had some experience in the area (most recently around four years ago when I etched not one, but two sets of double-sided detail parts for 1/100th scale T-72 tanks), I decided it was time to dust off the old equipment and get cracking. This time I decided I'd try and take advantage of a few options unique to PCB etching (since I'm only doing single-sided boards!). 

Board etching in Ferric Chloride

Even More Pi? A Violet Ram's Head 2 Build!

So, for those few of you who actually follow the blog, have you gotten the idea that I love the Big Muff Pi circuit, yet? If you're a fan as well, I definitely recommend Kit Rae's page covering all of the different variants of this iconic effects pedal. It has been an absolutely indispensable reference as I've tried to go through and build many of the different versions of this stomp box! As I mentioned in my announcement a few days ago, I'll likely have a few pedals for sale in the not so distant future, and the initial ones are likely to be BMP clones - so continue to watch this space.

That being said, this particular pedal was all for me! For this build I've gone back to AionFX's Halo board. It is a great board, and there is a spreadsheet that lets you build literally any version of the pedal you'd like - it even cross references the component codes on the board to the component codes on the circuit diagrams on the Kit Rae page. I'd already built a couple of versions of the '73 Gilmour Ram's Head (one of my two original Halo builds and the home etched PCB), a Russian Civil War / Red Army variant (also on a Halo board), and a Triangle (on a Tayda board). I'd heard great things about the Violet Ram's Head versions, especially the 2nd version, so I decided to go that route for this build. 

Aion's IVP Preamp - Tough Build, But So Worth It!!!

The complexity of effects pedal builds varies widely from circuit to circuit. Some of the most ubiquitous pedals out there, like the Big Muff Pi, are relatively simple circuits and fairly easy builds - at least in stock configurations. Component choice and modifications can, however, raise the level of difficulty quickly. Then there are other builds that you know are going to be turning things "up to eleven" in more ways than one. The AionFX Blueshift / Boss Dimension C DC-2 clone I built last year was incredibly complex - though AionFX only lists it as an Advanced (4/5) build (honestly I'd quibble with that...). I was looking for a unique challenge and I wanted to build up a few pre-amps to use with my planned computer recording interface. I'd built PCB Guitar Mania's Wolfgang 5051 pedal, and while it is a gain monster, I was looking for something with a bit more flexibility. Enter AionFX's IVP Preamp - one of their few builds that gets the full Expert (5/5) difficulty rating.

Apocalypse Now - Aion's Meteor (Ibanez SD-9)

The 70s and 80s saw an explosion of pedals, especially distortion pedals, hitting the market. One of these was the Maxon / Ibanez SD-9 Sonic Distortion pedal. The circuit itself has quite a bit in common with the Boss DS-1 or MXR Distortion+. For this project I used the AionFX Meteor board - which like the Plasma board I recently built - is available in legacy (no bypass board) and new formats. I went with the most recent version of the board with the 3PDT bypass daughterboard. As with many classic pedals, this one doesn't appear to be in production anymore, though you can get used models for around $200.

Colorsound Overdriver - Vintage Boost!

The Colorsound Overdriver is an early boost pedal from 1972 that quickly found its way into the hands of guitarists like David Gilmour and Jeff Beck. I'm a big Gilmour fan (just in case my recent DG20 Strat build didn't make that abundantly clear!), and really wanted to add this particular pedal to my board. These gems appear to be out of production at this point, and even later versions from the 1990s appear to be going for $500+ on Reverb, so this pedal is an ideal candidate for cloning. AionFX has a PCB for this particular pedal marketed as the Plasma. There is a modern version which just builds the Overdriver, and a Legacy version which will do the related Power Booster circuit as well. For this build I went with the more recent incarnation of the board and decided to do the Power Booster as its own build later.

PCB Mania No Noise Gate - Dang Useful Utility Pedal!!!

Readers of this blog should be well aware at this point that I'm a fan of high gain distortion and fuzz pedals. I'm also a fan of vintage transistors actually used in those high gain pedals. While you can get some absolutely amazing tones using high-gain distortion effects, you can also get a lot of tones you don't actually want. The most common is a hiss (high or low pitched) or a hum, though there are other unwanted noises that can detract from your sound. Given the prevalence of the issue, it should be unsurprising that there is a solution out there - Noise Gates. Many companies have produced a variety of pedals that essentially act as a high-pass filter - louder tones, i.e. what you actually want to hear, sail through while the softer hiss tones are filtered out. In this entry, I build PCB Mania's No Noise Gate - which is based on the Electroharmonix Noise Gate. The current EHX Silencer pedal is a bit more capable as it includes an effects loop rather than simply acting as a filter.

Component Organizing Day and Announcement!

Every few months I've generally collected enough parts to require reorganization of the stash. At this point I have a set of parts bins for diodes, ICs, and transistors that I use to keep track of everything. I tend to try and buy in bulk when possible to keep costs down, and I prefer not to have to go on hunts while building a pedal!

EMG DG20 Partscaster Build

Fender electric guitars - especially the Stratocaster and Telecaster - by virtue of their construction lend themselves easily to modification. The necks bolt on, and in many cases the pickups are housed within the pickguard itself - so any modifications required fit a new pickup or even a totally new style of pickup don't require the skills of a high-end luthier. This fact quickly led to the birth of the "partscaster" - any Fender guitar that has had parts swapped, or even guitars built from parts from the outset. 

Prior to this build, I owned one Stratocaster - an overall black one with cream pickups - and yes it looks a lot like "The" Black Strat. As I'm (obviously) a David Gilmour fan, I also wanted to have a strat with the EMG active pickup set he started using in the mid-1980s. That being said, my existing strat is a special edition, and I kind of want to keep it stock. I therefore started looking for a way to build my own "partscaster" centered around the EMG DG20 electronics.

Anasounds Trémolo - A Decent Teaching Pedal

There are a lot of different sources for guitar pedals and kits out there, but one I've come across recently, Anasounds, is just a bit different in a lot of ways. They only have two kits available, well, technically three, but I'll come back to that, and they appear to be mostly focused on hand-built pedals with a fairly wide range available. However, with those two kits, they demonstrate a major focus on the "how to" part of pedal building, including understanding the circuit, tracing it, and really understanding the underlying electronic principles. Their instructions are extensive including methods for testing the circuit at every stage of the build - which is very cool! The downside is that if you go by the instructions, you're building the circuit boards in sub-sections - which can lead to some challenges later on getting components to fit in tight spaces. I've built both of their main kits at this point, and this blog will feature the first build - the Anasounds Trémolo.

P90 SG Custom Build - Finally Finished!

In late November I wrote about my first custom DIY guitar build, but at that time there were still a few important "bits" missing to truly finish the project. I was still waiting on a custom truss rod cover and toggle switch plate (AKA "poker chip") that were on order, but hadn't yet arrived. I was also trying to figure out how to get a custom pick-guard made for the guitar as Warmoth didn't offer one for the Diamondback body. However with a little work I was able to get a pickguard made and now the guitar is finished. I may eventually sign the back of the headstock or something, but all of the pieces are finally in place.

More Pi - Two New (for Me) Takes on the Classic Effect

The Electro-Harmonix Big Muff Pi remains one of the most popular and ubiquitous pedals out there. In a previous blog entry, I'd built up two of the Aion FX Halo boards in different configurations. I had a lot of fun with the project, but given there are over 20 variations on the BMP circuit I figured there was room to add a few more flavors to the stable. While I was at it, I decided to look at other board sources as well (though there will likely be more Halo variants coming out in the future!). One of the boards I built up was a Tayda Big Muff DIY board. It's relatively inexpensive and tiny, but the instructions do come with component lists for seven different variations of the board. The second build was a bit (read a lot) more ambitious. A friend and fellow pedal-builder from Kansas City sent me a bare bones board he'd etched for the Ram's Head Big Muff based on the pattern from the Effects Layout blog. I've done some of my own photoetching for hobbies - I first learned from the gurus at the Ohio State University Chemistry department's electronic shop - but I've never etched my own PCB. Therefore, this was the first time I'd attempt to use a truly "old school" board. That being said, now I've now found a completely new rabbit hole to go down - so look for some "home brew" stuff in future blog entries!