Friday, April 26, 2013

So ya thought ya might like a DIY dude?

Basic DIY parts - Boards, resistors, capacitors, semiconductors and wires
Today I figured I'd do something a little different. Instead of bragging about another Fuzz I built and sharing my thoughts, I thought it would be a good point to stop for a minute and share some of the DIYer's daily routine. 

I've been an electronics geek since I was 9 and by the age of 11 I already had more than a few solder iron burns on my hand. I built mostly DIY kits and I was happy. around the age of 20 I started getting into electronic music and musical gadgets. Over the years I've built PAiA kits which came out excellent and have proven to be very useful and great sounding musical tools. It was only 3 years ago or so that I started really getting into guitar DIY pedals and amps. It all started with the Ruby amp by ROG and the Noisy Cricket from Beavis Audio. The amount of blogs, websites, tutorials and general info I found was so overwhelming that there was really no way back. At the time, I had a few commercial pedals like the TubeWorks Real Tube Overdrive, the VOX 847 Wah pedal and the fantastic Ibanez DD7 delay (which was the best birthday present I got from my wife after it was stolen during a gig). After a few fuzz and overdrive pedals I knew I would never buy another commercial grit pedal and the quest for the perfect fuzz circuit began. One thing I must admit is that I always wanted to build a spring reverb effect and have yet to achieve that. I did get myself this year (birthday again) the TC Hall of Fame reverb pedal which is an excellent addition to my ever growing rig.

So let's get down to business....If you're a noobe, a rookie, or just a dude who is trying to make a pedal in the real world, here's a short review of what you will need, and what you will need to know to get the job done. I wouldn't call myself a super experienced veteran, but I did build about 40 pedals and other audio gadgets over the past years and I made a hell of a progress over this period.

My 10 commandments for the DIY beginner:
  1. You don't need to be an electronic engineer to build a pedal, but you can't built anything right without having some basic understanding of electronics. You need to know what a resistor is what are capacitors, diodes, transistors, voltage, current, inputs, outputs, switches and potentiometers. All the rest can wait.
  2. You have to have soldering skills. Get a solder iron (or gun), watch some tutorials on YouTube and practice a little. It's not rocket science.
  3. Listen, learn, read-on....there are so many great websites with helpful information, use it! some of the best out there are:
  4. Decide what do you want to build, what sound do you want to achieve, don't build something you don't need. You don't want to spend money and time on something that you don't need or don't like. Listen to demos and watch videos of the pedals you are going to build. Almost any pedal you can think of has demo clips on the web. The gearmanndude YouTube channel has an incredible amount of pedal demos, so does Proguitarshop. Want some fantastic blogs except this one?
    • there are so many others too...
  5. Get all the information you need off the web BEFORE you buy any parts and BEFORE you do any soldering. Make sure you have the right schematic and a verified layout, compare versions and make a list of ALL the parts you need. It's really annoying finding out you need one more 2N5457 and having to wait for it to arrive by mail with your circuit sitting around almost finished. Great sites for buying parts:
  6. Get yourself a breadboard and make sure you are gonna build something that really works.
  7. It's harder to debug a non-working circuit than to build a new one. When you build your circuit make sure you are doing it right. Check and double check and triple check each point and don't move forward until you are sure you are OK. Go slowly and patiently. It will save you time.
  8. Nevertheless, there is always some probability for bugs. Bad parts, bad soldering, wrong schematics or just plain human mistakes. Don't loose it and be patient. Never give up on a circuit.
  9. Get yourself a simple digital multimeter and build an audio probe. The multimeter can test part values like resistance and capacitance but it is a super important tool for measuring contacts and voltage values. About the audio probe, we'll get to that later, but it's really something which helped me troubleshoot a few circuits. Any help you can get from articles by guys like R.G. Keen, Jack Orman, Doug Hammond, Runoffgroove and Mark Hammer can be extremely useful, but sometimes they  for more experienced DIYers. I built my audio probe according to the dubugging article:
  10. Last but not least..... Aesthetics is really something you should try to improve over time. It is great to buy good enclosures and to choose nice knobs, but what I really mean is keep your wiring neat and tidy. Shorter wires, better layouts, better enclosure and off-board wiring will make your pedal look better, and more important, it reduces noise, hum and can make your pedal sound better in the end result.
Solder gun, wire cutter, needle nose pliers and some
 solder wire. 
So....putting it down to practice. Say you made your mind on a great fuzz unit which you heard over on YouTube and you think that this pedal can do your tone some justice.
The audio clips on the Runoffgroove website or their older site home-wrecker are a great place to begin.
They give you everything from the clip and review to the schematic and the layout with a part list. The amount of schematics and layouts on the web is enormous and confusing. The websites I refer to on the lists above a great selection of verified schematics and layouts.

A breadboard setup with a bypass switch and i/o sockets
It is always recommended to start with a simple layout. Fuzz and booster pedals are a good place to start. It's good to order more parts than necessary for a specific pedal, over time you will see that you have many parts and can build a circuit from parts you have without having to order anything. For pedals which I wasn't sure about, like germanium fuzzes where the parts need tweaking, I found it very useful to get a breadboard and build a modular setup where I could use the breadboarded layout as a pedal with a switch and jacks so that I could really play with it and tweak it on the board.

Off board wiring parts...the enclosure is missing
Once you have the part list, don't forget to add the necessary parts for the off-board wiring and the enclosure. This means that for every circuit you see on the web you need to add:
  • 3PDT stomp switch
  • Enclosure (preferably metal)
  • Input and output sockets
  • 9V DC socket and/or a battery clip
  • Knobs
  • LED with a resistor
  • LED bezel
  • Stranded wire
Sometimes these must have parts are more expensive than the circuit itself.

Another thing that I found myself bashing my head about was 'what's the best true bypass switching layout?'
I found many layouts on the web and having tried more than a few I can safely say that I have found the right one for me. The layout below has true bypass switching with LED, DC 9V input with batter clip option. It also has input to ground connection when the pedal is bypassed. There are other options but this is what Analog mike of Analogguru and Zachary of ZVex are using. That's a very safe and sound layout.

My best stompbox True Bypass wiring scheme

An Audio Probe tester
The next thing is troubleshooting a bad circuit. You got everything hooked up, you think you got everything right, you plugged in your guitar, hit your favorite version of E with the pedal bypassed. Then you prayed and pressed the stomp switch but everything went dead. Then you panic....well...Don't panic! These things happen. Maybe you forgot something on the way. Maybe your transistors are busted, maybe you just didn't plug your DC power, but maybe it's something more complicated. 2 things you need: A multimeter and an audio probe. The multimeter can help you probe voltages and shorts anywhere on the circuit but a really simple way to find where your problem is is the audio probe. Just plug the jack to your amp or soundcard and the alligator clip to the circuit ground and then move from the output of the circuit backwards touching with the probe (the end of the cap) on the signal path until you find where the circuit becomes dead. One time I had a bad IC mounted and one time it was a bad solder point. It could be anything. Then the multimeter comes in to finish the job. Another thing is the grounds. Always make sure you got everything grounded right. It's easy to forget.

Drill protection with masking tape
The final stages of building the pedal are mostly aesthetic and artistic. I usually buy the Hammond style enclosures because they are strong and not too expensive. However, other metallic enclosures like chocolate boxes and mini lunchboxes, gum packages and other have proven to be equally nice, cheaper of-course, but naturally, not very sturdy.

When I want to drill the pots, switches and socket holes I learned that it's a shame if the die cast coating gets scratched during the drilling process.
The perfect enclosure

I started covering the enclosure with masking tape and did all the pencil measurements and drilling with the tape protection on. Once you are done drilling and cleaning, you take the tape off and the enclosure remains intact.

Trying to fit everything
In order to get your circuit sitting nicely in the enclosure and have all the off-board wiring all neat and tidy you will have to mount all the off-board parts on the enclosure and only then start wiring the thing up. This way you can measure lengths correctly without having excess wire running around in the housing. On longer wires you don't have to wire up wires on the shortest path but on a longer path so that the wires run inside near the edges of the enclosure and are not crossing diagonally inside. Sometimes there are so many wires that it simply looks a mess. Do the best you can. It's not easy making a pedal look good inside. Shorter wires and well organized wiring layout will help your pedal sound better and will help you troubleshoot problems if they occur in the future. Wires take up a lot of space. If it gets too crowded inside, your board can get messed up if you put pressure on it when you close the lid on the enclosure. Using shrink tubes where you think it is needed will prevent shorts. 

The finished product
So...that's it. Now that everything is working and you have chosen the right colors and played a bit with your pedal and you think you got yourself a keeper, you can commit to the artwork. After you paint the pedal there is no turning back, you won't be able to repaint it for another circuit (Unless you just paint VOL, TONE, GAIN).

For some time I've been looking for perfect colors to paint my enclosures, something which could be strong, opaque and comfortable for doing delicate brush work. What I have come up with is a set of window glass and ceramic paint. Lefranc & Bourgeois have some great ceramic paint, but the black color I found best was GlasArt used for vitrage painting. It says transparent but it is perfectly opaque for pedal painting. Buy a set of black, white, red, blue and yellow (maybe green too) and you can play around with a color palette to create some amazing tones. It is so much fun, if you enjoy creating new tones using various pedals for your guitar, you'll love painting. All the examples on this blog were done using these exact colors with Pure Sable brushes of various sizes. Acetone can be used to clean the brushes and to correct mistakes, but be very careful!!! Acetone can damage the gloss of the die cast coating so don't over do it.

Now go out and start patient...put some thought to it and don't give up if the first one doesn't come out as good as you through it would.

In the end, it's the love you put into those pedals that gives you that satisfaction when you play your guitar and you know that sound is really yours. 

One last warning before I wrap this post up....if you are a guitarist or any sort of musician, don't get caught in the pedal making business to much. It's better to burn out than to fade away....ha ha ....what I mean is - It's always better to play than solder.

Rock On...crew members

Thursday, April 11, 2013

Fuzz Testosteron

The Mastotron Clone. Even the LED is pink
Well, here's a quick one. I was asked by a friend to build a Mastotron Fuzz clone which would be just like the real ZVEX but in a PINK enclosure. The main specification he was after was ultra bassy fuzziness. Reading a little about this beast I thought this would be a good choice. 

The schematic and layout seemed like a modified fuzz face with some added controls. He also wanted to do the artwork so I thought why not. 
I ordered the parts and got straight away to work. I really got more and more into vero boards lately so I gave it a go and made a vero layout from the tagboardeffects blog using a regular prefboard and using the leads of the parts as connecting lines to emulate the vero board layout. I really like this idea. 

This pedal is not a legendary one nor do I know of anyone who used it in the history pages of rock...but this thing can really roar. Actually I've never heard such a great bass fuzz before. This thing is the perfect fuzz for stoner rock and doom metal guitarists who need their sound to explode with fireworks. It has the square wave character of muffs and faces but it has this extra grit that makes you go 'uhhhh'. The controls have PUSH/RELAX (just a Pregain), FUZZ (of course), PW (pulse width, a.k.a. smoothness), TONE (very effective) and VOLUME (actually not a loud pedal even fully CW).

knobs, from the left: VOLUME TONE PW FUZZ PUSH/RELAX
I went to give the guy his pedal down at an underground bar where he played with his band and they hooked up the pedal right there in the middle of the song, like they were waiting for it. The pedal sounded great right away (except for having a bit of a low volume).

I used 2N3904 silicon transistors which are supposed to be great, but if he asks for more volume I might switch to higher gain ones or just add a booster stage before the volume knob.

Again, I don't know too much about this one but it's not for everyone. It's not a muff or a face, it's really something else, which is very typical of the ZVEX line of pedals. He is always tinkering to get more options and a wider palette of sounds from his designs. 

Definitely a worthwhile design for fans of Witchcraft, Witch, Windhand, Cosmolux, Hellbender, Blowback and other Stoner/Doom rock bands. Did I say that I even had the LED ordered in pink?

Here is the layout and the ZVEX description of the pedal.

I did a demo using guitar and bass for this one: