Check out our MARCH MADNESS page for details on new pricing and how you can save money on MU synthesizer modules!
I’ve owned Q130 Clipper / Rectifier module by Synthesizers.com for some time now but somehow never managed to use it very much. That was mostly because I didn’t quite understand exactly what it did. I’d plug various sources into the module, turn it up and wonder if I was hearing a difference.
There are a few demos of the Q130 on YouTube (thanks for those guys!) but after viewing them I still wasn’t quite sure what was going on to the signals which passed through the module. Reading the docs (who reads those?!?!) helped but nothing clarifies things like a picture on an oscilloscope.
I happened to have my scope hooked up to the modular yesterday for some oscillator calibration so I took the opportunity to connect it to the Q130 and to see what was going on. I made two videos of the process; In Part 1 I connect a Q106 oscillator to the Q130 to demonstrate what the module does to an audio signal. In Part 2 I connect a Q109 Envelope Generator and we see what happens to the envelope.
I’m including the videos here for your dining and dancing pleasure. I hope you find them helpful.
Long & McQuade Owen Sound
Canada Drone Day 2017
Join Long & McQuade on Saturday May 27th from 1:00 to 3:30 as we celebrate National Drone Day 2017. Created by the Weird Canada and now in its 4th year National Drone Day celebrates drone, experimental, and ambient music at locations across Canada.
There will be performances by drone artists as well as a community drone session where everyone is welcome to join in and drone together. Bring your own electric or acoustic instruments or bring along a droning device or use your voice and join the session. There will also be instruments available for use in droning.
The event will be hosted by Lower West Side Studio and is suitable for all ages.
This is a free event! There will also be prize draws with ticket proceeds going to support addiction and mental health care. Don’t miss this exciting event!
Follow @longmcquade @drone_day @lowerwestsides
On Saturday March 25th at 2:00 join us at Long & McQuade in Owen Sound where we will be presenting An Introduction To Modular Synthesizers and Synth DIY.
Topics that will be covered include;
- Differences between modular synthesizers and normalized or preset synthesizers
- A comprehensive look at various module functions
- A detailed breakdown of each module’s use in a patch.
- The elements required for getting into Do-It-Yourself synthesizer module building.
Admission is free and the discussion is suitable for all ages and experience levels.
Another year another retrospective look at what’s been going on at Lower West Side Studio. It was a really busy year featuring changes, new music and new products. Here we go….
Drums / Percussion
Lot of playing but few additions. There was a slight paring down of the live Pearl kit I use. Because most of the music I play live involves Classic Rock there isn’t a huge call for the 8″ and 10″ toms. Sure they add some flavour but dragging them around plus the heavy duty stand they live on is just extra work for me and for my band who graciously help move my gear in and out of our venues. I’m sticking with the 12″, 13″, 14″ and 16″ drums (plus snare and kick). That’s enough to satisfy most sonic requirements plus a little easier in the schlepp factor.
One new and now invaluable toy I picked up last year is the Tune-Bot drum tuner by Overtone Labs. For decades I’ve been a purist when it comes to tuning drums relying on ear alone to get the right sound. When the early tuning tools came to market I didn’t even consider them. They relied primarily on lug tension to get the drum head in tune. As most drummers know, however, some lugs are stickier than others. This makes using lug torque as a benchmark for the frequency the head vibrates at unreliable.
The Tune-Bot is different though. It measures the frequency coming off the resonating drum head as its basis for tuning. This ensures that despite the differences in lug tension the head is tuned equally around its circumference. Tune-Bot takes it one step further with their tuning application. The application allows you to specify details of your kit (number of drums, tom sizes) and tuning preferences (resonant head higher than batter or vice versa, resonance time, frequency). It will then provide you with a list of frequencies which you should tune your heads to in order to get the perfect sound. I was skeptical at first but I have to admit it really works well. I’ve been able to quickly tune my kits in a variety of different ways with this great tool. Some tunings I liked while others not so much but with a quick edit of the parameters and an even quicker re-tuning I could experiment with a wide variety of tuning options that would be much more difficult to do on the fly by ear.
The device is small, well built and easy to use both in the studio and live. In fact Tune-Bot has recently released Tune-Bot Gig with fewer buttons, a large display and a bright silver case making it easy to spot in your gear bag. The Gig model is also apparently good for both studio and live applications.
I don’t know about giving two choices to drummers though… It might cause brain overload : D Seriously though. The Tune-Bot is a great addition to our studio’s gear.
2016 marked the addition of a new service for Lower West Side Studio – production of analog synthesizer modules. This all began in early 2015 when I built a PAiA 4700 modular synthesizer. Modular synths were something that always intrigued me and having some background in electronics helped me get the project off the ground. By the beginning of 2016 I had acquired a Synthesizers.com modular and had already built some Oakley Modular components for the system. Throughout 2016 the building technique had been improved upon as well as the creation of silk screened panels. Over the course of the year I built over 30 modules for my synthesizer and several dozen for other synthesizer enthusiasts.
There are a large number of synthesizer PCB vendors and I have built modules from several different manufacturers. These include Oakley Modular Systems, Cat Girl Synthesizers, Barton Musical Circuits, Moogah, Stroh, Music From Outer Space, Hexinverter, DJ Thomas White, Yusynth and others. Many of these boards can be purchased from Synthcube.com and ModularAddict.com. Both companies are excellent to deal with and offer a wide variety of products. Oakley is available directly from the manufacturer who also is outstanding for support and service.
In addition to offering complete modules for sale Lower West Side Studio also sells screened and drilled MU format panels for DIY enthusiasts who wish to do their own builds.
You may have noticed that the LWSS website now has a Products Page where you can get more info on our offerings.
2017 is already shaping up to be a busy year with new products being added to our line of products.
2016 was a breakout year for modular synthesis in Lower West Side Studio. We went from a pair of small modular systems with more conventional modules to a 110 unit system with some powerful sonic features. This monstrosity has been named SWAN (Synthesizer With A Name) as an homage to the movie The Phantom of The Paradise which features the ’70s super-synthesizer T.O.N.T.O.
While the Moog Unit or MU format is less radical than its Eurorack counterpart, mainly because MU focuses on analog rather than digital modules, there are still a wide array of complex wave and voltage manipulation tools.
Extremely creative patches can be built using the modules available as there are really no rules for hooking up the wide variety of modules in the system. Learning about synthesis is very clear as you can follow the signal flow visually unlike synthesizers which perform numerous functions “under the hood”.
One drawback with modulars is that once a patch is created it is very difficult to replicate exactly once it is dismantled. For this reason we’ve been doing lots of patch sampling or recording as the sounds are created. Consequently we’re building up a large sonic library which is available for our various projects.
Modular synthesis is in high gear now and won’t be slowing down as we enter 2017. Presently a new portable system (Phoenix) is being developed to house another 33 modular units including a bizarre reverb unit dubbed the TLN-156 Neural Agonizer.
With so much to learn about modular synthesis less attention was devoted to slab synthesizers than in previous years. More patches were created for the Moog Sub 37 for both original and cover songs. Preset patches that come with the synthesizer are avoided in order to create sounds that aren’t used by other artists.
We did, however, add one new synthesizer to the stable. Arturia’s MiniBrute single oscillator, monophonic synthesizer doesn’t store presets but produces deep, rich sounds that are extremely pleasing and a lot of fun to work with.
The MiniBrute also comes in an SE version which contains a step sequencer as opposed to the standard MiniBrute’s arpeggiator. Fortunately one of the MiniBrute’s designers, Yves Usson (of Yusynth) released a software patch which will upgrade the standard MiniBrute to SE capabilities. The patch can be found on Yves’ Hack A Brute site. It should be noted that in order to run the SE upgrade the MiniBrute must have the latest version of firmware. The firmware upgrade can be obtained from Arturia’s MiniBrute Resources page.
One other modification made to our MiniBrute was the removal of the keyboard and the rehousing of the MB’s guts. This was done using GMUSynth’s SkiniBrute retrofit. The SkiniBrute retrofit is an easy modification involving removing the keyboard then replacing the electronics in a new wooden frame with a new bottom panel. There are a wide variety of wood types and finishes available and the quality is excellent! If your setup already has enough keyboards which can be used as MIDI controllers and you wish to conserve space this is a highly recommended modification.
2016 didn’t mark any huge changes in software. We’re trying to keep music making in the hardware realm here at Lower West Side Studio. That doesn’t mean recording. We still use Reaper and a number of audio plug-ins from Native Instruments and Waves. Making music, though, is being done with hardware. Synthesizers, drums, stringed instruments, etc.. are all being favoured over their soft counterparts.
One small addition to the software side of things in fact has to do with tuning hardware. A wonderfully useful app called VCO Tuner by TheSlowGrowth on the Muff Wiggler forum has streamlined the process of calibrating Voltage Controlled Oscillators being built. Without getting too technical the app controls the oscillator’s output and then monitors that output for analysis. It makes the process of calibration very easy compared to using an oscilloscope or doing it just by ear. Details on the VCO Tuner can be found on Muff Wiggler (the greatest modular synthesizer resource on the Internet) at this link.
A lot has happened in 2016 with both Fizzbin and Coming of Age.
Fizzbin has been focussed on creating original music in 2016 with much of the year’s rehearsal time being devoted to experimenting and music creation. John also added a Korg MS-20 to his synth setup and has come up with some incredible sounds.
Last year Fizzbin also performed live at the Mad River Rocks festival. The performance was very well received and we had a great time entertaining the audience. Our set consisted of a mix of both original and cover songs which were in contrast to many of the other (excellent) performers at the show. We hope to return this year!
Coming of Age had an interesting 2016 as well. After the summer where we performed at some events our lead guitarist Dave left the band. The departure was on good terms and we were lucky to have such a talented musician perform with us. Dave totally rocks!
Fortunately we were able to welcome a new lead guitarist, Darren, to Coming of Age. Darren brings with him years of live performance experience and together we’ve been expanding our repertoire and improving our musical skills. It’s great having him in the band!
December marked our first performances with the new line up including an outdoor concert at Collingwood’s Frozen In Time festival and Craighleith Ski Club’s New Years Eve party. Both were wonderful experiences although the former was quite chilly!
2016 also marked to reuniting of my old teenage heavy metal band. Through sheer luck I was contacted by Jim my old bass player. Jim coordinated communication between our lead guitarist Jason and soon we had the old band back together. Thirty-Six years ago we’re were called Menion but we’re not quite sure if we’re sticking with that name. To make matters more awesome Johnny G., CoA’s rhythm guitarist and vocalist is performing with us as lead vocalist (and rhythm guitarist). We’ve only had a few rehearsals but 2017 will be a lot heavier. It’s great seeing my old friends again and I’m excited to see what we’ll all be able to pull off!
So that’s what’s been going on here in Lower West Side Studio over 2016. It was a very excellent year for music and technology. 2017 will be even better!
This year Lower West Side Studio has produced over 50 hand-built synthesizer modules. Of all those modules the CGS49 from Cat Girl Synthesizers was the trickiest build. Let me explain;
Ken Stone, maker of Cat Girl Synthesizer modules, has some outstanding circuit designs that make for awesome synthesizer modules. A lot of times though the documentation leaves a lot of interpretation and options. Many times the information required for a successful build must be looked up and cross referenced in order to determine the best course of action of a build. I’ve found the best sources for this information are on Muff Wiggler’s DIY forum and on Electro-Music’s Ken Stone Designs forum. This is, of course, on top of the documents provided by Ken for the modules themselves.
The CGS49 Dual CMOS Filter or Wasp filter is one such module. The filter was designed based on Electronic Dream Plant’s 1978 Wasp synthesizer. The filter features the raspy, buzzing quality of the Wasp’s built-in analog filter. Even better, the CGS design features two filters which run in parallel.
To make the filter even more fun to use a Spread control voltage can be added to sweep the filters control voltages together. This can produces some very bizarre and unexpected sonic results. It also makes this filter far more flexible than the single filter versions of the module which are available.
When building the CGS49 I began with two PCBs which I built simultaneously as I often do when building multiples of a module type. Doing so helps me cross-check each board to ensure the correct parts were used and to verify if a bridged solder connection was accidentally done. I do this by saying “shit! I think I bridged that connection” and then checking the other board(s) to ensure those connections either should or should not be bridged. In some cases solder can flow across a trace line which connects two points so a solder bridge is fine in that case.
The build of the boards went smoothly although on board #1 a solder pad was lifted during the build process. This connection was repaired by jumpering the two points together with a short piece of insulated wire. I have worked on a large variety of PCBs over the past year of building and while I love CGS designs I have to admit the board quality is lacking. Compared to other boards with clear, dual sided solder pads the CGS boards come up a bit short. The CGS49 also has some portions of the silkscreen doubled and therefore unreadable. One must refer to the documentation in order to determine exactly what goes where. To make matters even more complicated, while Ken often includes a large black and white line drawing of the board in the documentation the CGS49 features only a blurry coloured image which is more difficult to read. Still, this didn’t make the build too difficult.
Where things got tricky were in the wiring of the Frequency potentiometer and Spread potentiometer. In the CGS documentation it states;
“It has been suggested that connecting the frequency pot between +VE and -VE instead of +VE and GND as shown will allow the filter to be used at lower frequencies. If doing this, you may find it beneficial to change the wiper resistor up to 270k, or add an extra resistor of 150k in series with the wire from the wiper to the PCB.”
From what I read and learned for myself this is not merely a suggestion and must be done in order to get the module to function correctly. I found that wiring the lug 1 of the frequency pots to the -15v ferrite bead worked well for this purpose. Make sure though to wire to the side of the bead further from the power source so that the current has passed through the bead before passing to the potentiometers. I chose to solder my wires to the bottom of the board at the solder point of the bead. The connection was very secure and it looks more tidy. BE VERY CAREFUL not to let any exposed wire from these runs be left or they could touch some other component and zap it.
When wiring the additional 150K to the wiper connection of the potentiometer I suggest you wire the resistor in line with the wire and encase the connection in heat shrink. If you wire the resistor at the potentiometer’s lug you run the risk of the resistor bending over and touching the -15v connection. You could also just substitute a 250K (or 270K) potentiometer for the 100K one indicated in the documentation.
The Spread potentiometer wiring is also a bit tricky. Two wires run from lug 2 (the centre lug) of the potentiometer. One runs to the CVSN connection pad on Filter 1. This connection must have a 100K resistor wired in line. Again I suggest wiring the resistor into the line and then heat shrinking it rather than connecting the resistor to the pad. The second wire must connect to the junction point of the Filter 2 TL072’s pin #3, the 2K2 resistor connected to it and the 100K resistor connected to them both. This is actually easier than it sounds. You can wire the lead to the side of the 2K2 resistor which connects to pin 3 of the TL072. Again, I wired this to the solder connection on the underside of the board. Make sure to expose only the necessary amount of wire from the shielding to prevent shorting.
One other thing to note is that there are ten (10), yes, ten jumpers to be soldered to the board. If you miss one as I initially did you will have a board that does not function correctly. In my diagram of the PCB I have labeled them as J1 through J10.
Sounds a bit difficult, yes? It really isn’t but hunting down the information and then testing the options can be. That’s part of the reason I’m writing this article and I hope it provides some help to other builders of the CGS49.
During my build, unfortunately, I must have done something bad to my #1 board. Things worked then didn’t work. Then they partially worked. I swapped chips, I replaced caps and I tested parts. I also created several diagrams which I will share here. The CGS boards list the part values on the board rather than identifiers such as R1, R2… R42, etc. This makes for easy building but difficult debugging when you try to reference a part to others for support. I created a reference scheme for the CGS49 and then associated the parts with their location on the schematics. Here are the diagrams;
NOTE: You can right click the images above and download them to obtain higher resolution copies
After attempting to debug the first module for over a week I decided to shelve it and proceed to wire the second module I built. This module worked perfectly the first time further leading to believe that I blew up a component (or components) on the first board while playing mucky-muck with the -15v lines. I’m going to go back for one more look but in the meantime I’ve ordered another PCB.
I installed the CGS49 module in a 2U MU format panel I designed. The design utilizes 20mm knobs which are not my favourite for MU modulars and I might try to re-work my design to make enough space for the 25mm knobs I prefer. In any case the filter has a very unique sound and really adds a lot to the system. I’ve created a short video outlining its capabilities.
Ken Stone’s Cat Girl Synthesizer modules are definitely not builds for beginners. They are, however, fantastic additions to any modular synthesizer and I highly recommend them!
EDIT: Here’s the panel design with the 25mm knobs
DIY modular synthesis has become very popular as more and more vendors offer printed circuit boards (PCBs) which can be populated to become synthesizer modules. Some of these PCBs even come in kit form which includes the board, component parts and a panel. Many, however, come as a standalone board leaving it up to the end user to obtain the rest of the items required to complete the module. This option is (arguably) the most cost effective method as it gives the builder the choice of component vendors and purchase quantities. If you are planning on building several modules buying electronic components in bulk a very good way to keep your modules cost down.
Panels, however, are a different story. Mention panels to many modular builders and they’ll cringe. Often times, at least for me, obtaining a panel to house your electronics is the hold-up point for the project. Many fine vendors out there sell finished panels which include the graphics for the potentiometers, jacks, switches, lights, etc… along with the pre-drilled holes to mount your parts into. This is a great option for builders and while it does add some expense to the project, the convenience of being able to order the panel and then finish the build is worth the cost.
Sometimes, though, with the addition of shipping expenses, taxes and currency conversions a panel which is priced very reasonably by the vendor can end up costing more than the electronics portion of the module itself.
I have gone through a number of options for obtaining panels for my builds; I’ve purchased panels from vendors who produce them for sale. I’ve had them screened by a local printing company and I’ve produced them myself through the process of silkscreening. For me the first two options have been very cost prohibitive. If building one-off versions of the modules for myself this is sometimes a viable option but if building the modules for sale to others it drives the construction price right out of the market. Ultimately I discovered that producing the screened panels myself has been the best option for me.
The silkscreening process can seem very daunting and I personally found it that way. Through trial and error as well as some online support I have managed to work out a process to create my own screens and screen the panels themselves and finally to drill out the panels for installation. By keeping the items I require on hand I’m able to produce finished panels in a very short time (less than half a day). This article is meant to share some of my experiences with other builders who wish to screen their own panels.
Before I begin I should note that the process I use is for MU (Moog Unit) format panels. For MOTM style panels I have used FPD files and Front Panel Express where I have obtained excellent results at reasonable costs (plus they ship gummi-bears with their orders). Mmmmm gummi-bears.
Following my adventures in having a local printing company screen the panels for me (at a very high cost) I decided to screen panels myself. I purchased panels from Synthesizers.com so I could be sure the size and quality was spot on. The next step was to obtain the silkscreens with the images of the panels which I produced using Microsoft Visio. I have been using Visio since it came out and I’m quite familiar with it. I even created a small library of the shapes I frequently require. These include knob graphics (0 to 10, -10 to 0 to 10, no numbers) as well as graphics representing jacks, LEDs, switches and more.
I found a company that would produce the screens for me from SVG files (Standard Vector Graphic). Because of the fine lines and small letters and numbers used on the panels I chose a screen mesh count of 230. That is 230 threads per inch. Lower mesh counts work but like lower resolution on monitors, fine images get a chunky, unappealing look.
The trouble I encountered was that the screen production company was manipulating the graphics files I was sending. This was mainly to fit two panel images on a single screen. In several cases the graphics were not lined up correctly or some of the text and images were changed or omitted. Vertical text sometimes had words run together despite the original version being correctly and meticulously laid out. The biggest problem for me, however, was the large cost of shipping the screens. Some of the screens were used for personal one-off panels and these once again made the process less than cost-effective.
The process of creating my own screens seemed daunting but after a bit of trial and error I’ve been able to do it with good results. The first step was finding a company to purchase the screens from. I located a company just outside of Toronto (I live about 100 miles north of the city in a rural area). They provide ready made screens in the mesh density I desire. I use a standard 20″ x 24″ framed screen. They also sell the emulsion, emulsion remover and other supplies necessary to produce the screens.
I should mention that I first tried using my own hand made screens along with a kit I picked up at a local art supply chain (Michaels here in Canada). The kit was by a company called Speedball and it contained small sizes of emulsion, remover and a screen (110 mesh count). I had also purchased some squeegees spatulas and a roll of 230 mesh from a mail order house to make my own screens with. I purchased some small framed canvases at the art store, removed the canvas and stapled the 230 mesh to the empty frame, stretching it tightly. While this did work out the tension was nowhere near what a good quality screen should be so after making a couple of panels with this setup I switched to professionally stretched screens.
When I made my mail order purchase early on in my learning of the process I also purchased some film emulsion. This could be cut to size then applied to the screen with a two step spray on adhesive. I thought this would be easier than the process of using liquid emulsion. It wasn’t.
The Speedball emulsion that came with my kit was far easier to use. The emulsion is mixed with an activator when first opened. The mixed solution can stay usable for several months if refrigerated and even with the small quantity contained in the kit I was able to produce several screens. After running out of the Speedball emulsion I switched to Chromaline UDC-HY. I was able to purchase a larger quantity of it for a much better price.
While the best way to apply the emulsion to the screen is with an emulsion applicator ( a trough-like device that evenly spreads a thin layer of emulsion) I was able to use a 9″ squeegee with a good degree of success. Remember to keep the layer very thin and very smooth. Any imperfections will affect your screening process.
Make sure to allow the emulsion to fully dry before proceeding and keep the emulsified screen in a dark place once it’s dry to prevent exposure. I would apply the emulsion in a lighted room but once the emulsion was applied I would move the screen into a dark room to dry and then transfer it to a closet until needed. Using a red LED light bulb in that room was handy for avoiding bumping into things in the dark.
It’s also a good idea to have emulsion remover on hand in case your emulsion job goes awry or in case you just want to reuse a screen. This is typical when making a single screen for a single, one-off panel.
The Film Positive
To create the image for the screen I printed my graphics onto transparency film. This is called a Film Positive. The transparency film is available at your local office supplies store. It costs a bit of cash but is well worth it.
While there are many types of professional films for Film Positives I’ve found that regular transparency film works fine. The critical thing to make sure of is that your inkjet printer has a good, full black ink cartridge. If the image printed is not solid enough light will pass through during exposure causing a poor screen image. I’ve tried using two copies of the same transparency laid atop one another and taped on the edges but this can cause distortion if the two transparencies aren’t perfectly aligned. Generally a single well printed transparency will work just fine. Make sure your inkjet’s black toner is fresh and well topped up and that the print head is clean. Be sure to let the ink dry before moving around the output as well.
Oh, one last tip; some transparency film comes with a white strip on one edge for handling the transparency without getting fingerprints on it. I recommend cutting this off with an Exacto knife (or similar) as it will create a big blank line on your screen into which ink may accidentally seep through. Not critical though.
When reading about the screen creation process I read a lot about light tables and other complex methods of exposing the emulsion to light. I ended up finding a video that showed me how to create my own exposure lamp using some 2″ x 4″ wood and a halogen work light. Even this is not fully necessary and exposure can be performed with good old sunlight.
I found this video online which was very helpful for building an exposure unit for an extremely low cost.
This exposure unit has worked great for me.
Exposure time is another factor when preparing your screen. At first I would get exposed screens but the emulsion would not wash out of the printed area. This was because I was exposing the screen for far too long. I found that for my exposure unit and the emulsion I was using that four (4) minutes of exposure time was perfect.
I watched the following video to learn a technique to determine exposure time (the whole video is good although I’ve time indexed the exposure section)
Again, when working with the screen in preparation for exposure I had a red LED bulb on in the room just to prevent accidental exposure during handing.
Finding the right ink was a challenge which turned out to have a very simple solution. At first when I was having the screens done by a professional printing company they told me that a big part of the cost was in determining the appropriate paint to screen with as the surface was metal.
Actually the surface of the Dotcom panels is powder coated paint which holds the screened ink quite well. When obtaining my own screens then experimenting with material I started with acrylic paints. I chose acrylic because it was easy to handle and washed off with water. If I messed up a screen I could wash the error away if I got to it within a minute or two. Warm to hot water was good for this. The trouble was the different paints I tried were all a bit too runny and yielded poor results.
I finally tried Speedball Screen Printing Ink for Fabric (white). This turned out to be an excellent choice. The ink was thick, bright and was easy to handle and to wash off. Remember to keep your squeegee, spatulas and particularly your screen very clean.
The real trick to ensuring good adhesion with the ink is in the curing process. More on that later…
The Screening Table
While many sophisticated screening tables are available for big bucks I was looking for a more cost effective system. Using some scrap wood, a pair of screws and (most importantly) two Butterfly Hinges ($5 each) I fashioned a device which would allow me to screen my panels. The system works just fine for single colour screens and while I wouldn’t recommend it for high-volume production it works great for small quantity panel creation.
The screen itself should be about 1 millimetre above the panel itself. This allows only the portion of the screen under the squeegee to be touching the panel at any given moment and avoids smearing. I use a pair of screws in the table which the frame of the screen rests on. They are positioned at a depth allowing this 1 millimetre gap.
The Process – Part 1: Emulsifying the Screen
Mix the emulsion with the activator according to the instructions for your particular brand of emulsion. Mark the container with the date so you’ll know when it expires as you don’t need a whole lot of it for each screen. I use a large Zip-Lok bag to store the container in the fridge after I’m done. The bag prevents stray emulsion which may have got on the container from dirtying the fridge and getting my wife angry with me.
The emulsion may stain plastic wash sinks if left for any length of time so make sure to have a source of water and scrub brush handy. Latex gloves are also a good idea. I have a short length of hose with a garden spray nozzle connected to my sink to add some pressure.
Since I don’t have an emulsion applicator I use a squeegee to apply the emulsion to the screen. Emulsion is applied to the bottom side of the screen. That is the side the screen is attached to frame. The side that makes contact with the panel. Apply a thin even layer to the screen. If you have to go back and forth just make sure the layer is even and smooth. I don’t cover the whole screen as I’m only using a panel-sized graphic (smaller that 8.5″ x 11″).
When I apply the emulsion I squeegee the emulsion right off the edge of the screen into a large aluminum tray that I place in my laundry room work sink (see: keeping the wife happy). I can then recover the excess emulsion and return it to the container before refrigerating it for storage. Plastic paint spatulas are ideal for this.
Once satisfied with my layer of emulsion I place the screen bottom side up on a table in my dark(ish) room with a fan which gently blows across the surface. If the layer of emulsion is thin and even it should dry in one to two hours. If you have a bead of thicker emulsion down the sides of the emulsified area (caused by the edge of the squeegee) I carefully remove it with my paint spatula to avoid a wet thick section which takes longer to dry. Just make sure not to muck up the smooth centre area where the panel image will ultimately go.
Once dry you can either proceed to the next step or store the screen in a cool, dry, DARK place until you need it. Sometimes it’s handy to make several screens if you plan to create a bunch of different panels.
The Process – Part 2: Screen Image Creation
Double check, then triple check your image ensuring the spacing is correct, fonts are suitable and that the spelling is correct. Print on plain paper first and stare at your panel design. Sometimes mistakes make it through to this stage. Have someone else check it for you as a fresh pair of eyes can spot errors you miss or see logistical problems you didn’t foresee. Also remember that you don’t want to print the image of the panel if you included that in your design. You only want the text / graphics which will be screened onto the panel plus crosshairs for where drilling should be done.
Once the graphic is confirmed ready on your computer print it onto transparency film. Let the ink dry thoroughly once printed and avoid bending the transparency so that the ink doesn’t crack.
The next steps involve using the exposure unit I chose so this process may differ from other systems. First, I place a piece of black cardboard (available at your local office supply store) across the bottom of my exposure unit. This prevents light from bouncing back up and ruining the exposure. Next I place the screen, bottom up onto the cardboard and place my film positive UPSIDE DOWN onto the screen. It is upside down because when the screen is turned over it will be in the correct orientation. Finally I place a piece of glass over the film positive to ensure firm contact between the film and the emulsion side of the screen.
And now… LET THERE BE LIGHT! I activate the halogen light and at the same time activate a 4 minute timer. Actually I have SIRI activate my timer. At this point I also turn off the red light and turn on the room light. After all, we are exposing using light so what the heck.
At the end of 4 minutes I immediately remove the glass and Film Positive from the screen and take the screen to sink where my hose and nozzle is set up. Sometimes in the summer I do this outside. Whatever you do, don’t dally (who talks like that anymore ; )
First I spray each side of the screen very quickly and for just a second in order to wet it down. This starts the exposed areas to begin to appear through the emulsion. Then after 10 to 15 seconds I begin to spray the screen to wash out the exposed areas. Use only cold or lukewarm water (tending towards cold). DO NOT USE HOT WATER. I use the “Flat” setting on my nozzle which generates a wide, flat fan shape from the nozzle which has a good deal of pressure but not the heavy duty maximum pressure. Spray from the top of the screen through. You’ll be looking at the correct orientation of the text if you’re looking at the top (providing you didn’t screen the Film Positive backwards : ) You only want to wash out the exposed area, not blow all the emulsion off the other side. You also don’t want to damage fine areas like lettering, numbers and knob graduations.
When done correctly you should be able to see through the mesh where the exposed areas have been removed. There should be no emulsion remaining. Watch for “cloudy” areas where a thin layer of exposed emulsion hasn’t washed off. Again, be sure not to use too much pressure or to focus your water stream too much in one place or you could damage your work.
Once satisfied with the washed off screen I then place the screen back on my work table with fan to dry it off. This only takes about 10 minutes.
The Process – Part 3: Screening the Panel
With the screen all complete it’s time to put ink to panel. The frame of the screen must be snugly mounted into the Butterfly Clamps. The important thing is that everything not move during the process. Because I don’t use a specific positioning system when preparing the graphic on the silk screen I have to “eye” the location of the panel.
This involves carefully placing the panel beneath the graphic and carefully moving into the correct position. I also use a pair of aluminum rails to help firm up the position of the panel once it’s in place. This is a slow and carefully executed procedure. I use duct tape to hold everything in position.
I’ve also found that if only the panel is used on the table during screening there can be some smearing at the top and bottom of the panel as the squeegee pushes the screen down to the panel at these points. To prevent this I use 2 blank panels wrapped in cellophane (to protect them from stray ink) positioned at the top and bottom of the panel I’m screening. This acts as a buffer so the panel is printed more evenly.
When everything is in place I lower the screen and apply ink over the area of the panel. This ensures that the ink will cover everything and will not rely alone on the squeegee process to spread the ink. I also apply a bit more ink along the top of the panel to ensure that there is plenty of ink when the squeegee is used.
The next part goes smooth and quickly; firmly grasping the squeegee drag it down the panels (over the top buffer, down the main panel and across the bottom buffer). Apply even pressure all the way and be deliberate. Use a slight tilt to the squeegee so the edge of the rubber rather than the flat bit makes contact with the screen. Don’t use too much of an angle though. Don’t hesitate or lose your nerve during this portion of the operation. If a mistake is made you’ll have a minute or two to wash the panel off and try again. If everything goes ok (which after much trial and error it has been) then I lift the screen to check the panel then use my spatula to remove excess ink and place it back into the ink container.
The next part MUST BE DONE QUICKLY. Get your screen, squeegee and spatula to your wash area. Wash the screen thoroughly with cold or cool water. Make sure to get all the ink out of the exposed areas to ensure the screen can be used again. A thin scrim of ink will likely stick to a portion of the screen but as long as the exposed areas are clear you’ll be fine. Warm or even hot water can be used to wash your tools once the screen is clean and out of the way. If you wait longer than a minute or two to wash your screen there is a good chance it will be ruined so don’t hang around admiring your panel. Once you check that it’s ok do your clean-up quickly.
But what if it’s not ok? Something may have moved or perhaps your pressure wasn’t even. If this is the case first carefully remove the panel from your setup. You don’t want to mess up your positioning apparatus as you’ll have to put the panel exactly back into position for your next attempt. After the panel has been removed quickly use your squeegee to cover the exposed area of the screen with a very thin layer of ink. Don’t press hard with the squeegee as you don’t want the ink to go through the screen. You only want to cover the exposed area so that the ink doesn’t dry into it while you’re washing your panel.
Take the panel to your wash area and use warm / hot water and even a light scrub brush to remove the ink. This must be done quickly before the ink dries (on either the panel or the waiting screen). You must then dry the panel thoroughly, re-install it in your table and repeat the screening process. If it fails a second or third time you may want to remove the ink and execute the cleaning process on your panel, screen and tools before trying again.
It sounds complicated and takes some practice but with time you’ll find that it’s not that difficult and takes only a few minutes.
The Process – Part 4: The Curing Process
I like to ensure my ink has set firmly by “curing” my panels. I use a toaster oven dedicated to this process as there is a smell and thin residue produced that I don’t want in my oven where my food is cooked (and again, I don’t want to piss off my wife). I have found that 15 minutes at 320 degrees Fahrenheit does the job just fine. If you cure for too long or at too high a temperature the ink can turn an off-white brownish shade.
The last part of the process involves drilling the panel, filing off the backside of the panel to remove burrs and then installing the components. I won’t talk about this too much although I will say I recommend using a drill press and using pilot holes before drilling the actual holes.
So there you have it!
There are a lot of helpful videos on the Net which you may gain tips from which are helpful to your process. I learned a lot from them. I also learned a pile of info from Jeff at GuitarFool.com. It was his site and his support that helped me get my screening project off the ground. Thanks dude!
Remember that this is just “what works for me”. There are many ways to skin a cat (sorry Wigglers) and you have to find the right technique to suit your personal needs.
Author’s Note: I posted a link to this article on the Muff Wiggler DIY Forum. If you’re not already aware, Muff Wiggler is the FINEST resource on the Internet for modular synthesizer enthusiasts. There are some excellent points being made in relation to this article. You might find it interesting to follow this link and read them for yourself.
As you may have read in this thread, modular synthesis, particularly DIY modular synthesis came to Lower West Side Studio in May of 2015. The PAiA 9700 modular became the first truly analog modular synthesizer I had ever personally worked with.
Excited by this new / old technology I got more and more involved in the modular synthesizer world. October 2015 marked the addition of a Synthesizers.com modular system and things took off from there!
The initial system consisted of the components required to build sounds; MIDI to CV interface, Oscillators, Envelope Generators a Filter and a Voltage Controlled Amplifier as well as a Noise Source. These modules lived happily in a Dotcom 22U walnut cabinet on top of which I stacked my PAiA 9700.
Very soon after acquiring the new modular I got into the DIY world of building my own modules. Numerous vendors produce modules for 5U / MU format synthesizers and I began to build a great number of them.
Here are some of the experienced I’ve had with my modular synthesizers as well as the world of DIY.
There are several formats for synthesizer modules with Eurorack easily being the most popular and providing the largest number of modules. Personally though I prefer stick with (at least for now) the Moog Unit or MU format. From a usability standpoint I like the large knobs and switches and the clean, consistent layout of the panels. I also prefer the way that each module generally performs a single function. I find that it makes creating and debugging patches easier.
Eurorack does have a lot to offer though. The small form factor makes portability very easy. Coupled with the feature that modules often provide several functions per module you can take a lot of synthesizer with you in a compact case. The jangley graphics, tiny knobs and inconsistent format don’t appeal to me but a huge number of synthesizer users out there really prefer it. That is why the bulk of modules available are created for this format.
Cases / Cabinets
Presently my modular system is installed in walnut cabinets. The first cabinet I received, a 22U (unit) cabinet, was from Synthesizers.com. The quality and finish are absolutely beautiful. The problem with living in Canada, though, is that when most of the gear is manufactured in the USA or overseas there is a large cost for currency conversion, HST (yes our greedy government takes a cut of merchandise not even sold in this country) and of course shipping. Shipping 44U cabinets not to mention the other expenses makes them cost prohibitive. My solution was to find a local carpenter who could produce the cabinets for me and match them to the Dotcom finish so the entire system would appear as a single unit. Once I filled the 22U system over the Winter of 2015 / 16 I purchased a 44U cabinet for expansion. After building several modules (more on that later) I filled the cabinet and by late summer I had ordered a second 44U cabinet giving me a total of 110U and a wall of modules.
One very critical point to remember is power. My original Dotcom QPS1 power supply was not going to be able to power 110U worth of modules. There might have been a chance it would as just because there is 110U doesn’t mean there will be 110 modules. Running a power supply at its limit, however, does not yield the best performance so I replaced it with a QPS3 power supply.
As you can imagine this system is not very portable. While it could be moved from location to location it’s not something I would really like to do. For starters the cabinets are all bolted together so removing and reinstalling the connecting brackets would really wear and tear the wood.
Instead my plan is to build (or buy) a portable cabinet. I will use my displaced QPS1 power supply to power the unit. With a portable I can install modules required to produce sound on the go (VCOs, VCFs, VCAs, a sequencer and support modules) while utilizing it set up next to my main modular unit when it’s not on the go. The best of both worlds!
The Do It Yourself side of modular synthesis is very appealing to me. I got my start in the computer field decades ago by building Apple Computer peripherals from the PCB on up. Those skills translate very well into the world of DIY synthesis. MU format modules generally utilize Through-Hole components which are easy to handle and to solder.
The first synthesizer in the studio, the PAiA 9700, was completely DIY and is an excellent way to dive head first into this area. The 9700 is in FRAC format and while I was able to integrate the 9700 with my Dotcom modular through the use of 1/4″ to 1/8″ conversion cables it never seemed a true part of my system. To remedy this I mounted the PAiA modules in MU format panels and replaced the 1/8″ jacks with 1/4″ jacks. I also replaced the tiny potentiometer knobs with larger 1″ knobs (the pots stay the same though). Overall the conversion was quite simple.
Building new modules turned out to be both easier than expected and quite fun. There are numerous vendors providing Printed Circuit Boards (PCBs) for MU format or for multiple formats (which allows them to function in MU format systems). The important thing is that they run on +/-15 volts which is what the MU format (with the exception of Moog themselves) utilizes.
The bulk of the modules I’ve built since beginning the DIY adventure are by Oakley Sound Systems. I find their boards quite excellent to work with. The quality of the boards, their clear labeling and good documentation makes them easy to build. The best part is they sound and function outstanding. I have also built numerous modules from Cat Girl Synthesizers. The CGS modules are often quite unique and while not documented as thoroughly as the Oakleys are not too difficult to get completed. Because both of these manufacturers produce DIY only products they are not as widely found as say something like Synthesizers.com or other vendors (Moon, STG, COTK, etc…) who only provide full working modules. There are several companies (Lower West Side Studio for example) who will build these DIY boards for sale as completed modules.
I have also found some terrific vendors for DIY products. While Oakley sells their boards directly to the end user products by CGS, Barton, Moogah, Yusynth (to name a few) can be obtained from companies like SynthCube.com or ModularAddict.com. I’ve found both these vendors to be excellent at providing quality products for a good price and on time.
Now to the panels. The toughest part of DIY modular synthesizer building I have encountered is obtaining panels for the boards once they are built. Some companies such as FreeState FX and SynthCube.com sell finished, drilled panels for many popular modules. I have used several methods in obtaining panels including having them screened at a printing company but all have been quite expensive. I have been silk screening my own panels as of late and even produce the screens themselves. I will be writing a detailed article on this aspect of synth building in the very near future.
While most of my modules are built in-house I have a large number of modules which have been purchased ready-made. These (so far) are all by Synthesizers.com. There are a large number of MU format vendors out there but up until this point I have found everything I need with Dotcom products. From their oscillators to their sequencers I have not found a module I am dissatisfied with. Their products are excellent and their service and support is outstanding!
That isn’t to say that I won’t be buying modules from other vendors. While a wide variety of vendors each make oscillators, filters, amplifiers, sequencers, mixers and other similar modules they are all quite different from one another. In a way they are like cars. Sure cars have four wheels, an engine and a steering wheel but they are still all quite different. Similarly, different modules from different vendors all have their unique attributes. Some, for example, are workalikes of modules by very well known and respected manufacturers such as Moog, ARP, Oberheim, Korg and others. Other vendors have their own take on how modules should sound and perform. It is my desire to have a wide variety of modules from a large number of vendors to allow my modular to produce an extensive variety of sounds. At this writing my modular, dubbed SWAN (Synthesizer With A Name), has six oscillators from three vendors and eight filters from eight vendors and five amplifiers from four vendors.
Oh… And The Sound!
While I have heard a large number of synthesizers in my experience, nothing holds a candle to the wide ranging capabilities of modular synthesizers (except maybe the Minimoog). The extensive patching capabilities can’t be matched by slab synthesizers. The ability to select just the right filter for just the right oscillator and just the right support modules in any situation gives these synthesizers an ability to produce sounds that can’t be beat. Further, the degree of understanding that goes along with sound production grows as you delve further into each modules abilities. You can visually follow the signal paths and alter the sounds as you see fit. There are no rules for what can plug into what and therefore you can achieve sounds that are difficult or impossible to obtain otherwise.
Having said that, there is of course the difficulty in duplicating sounds once you’ve created them. There are a wide variety of methods of documenting patches but sometimes even plugging the right cables into the right jacks and setting the knobs the way you’ve got them written down doesn’t cut it in reproducing the sound you originally documented. Maybe the machine was on for eight hours when you first made the sound. Maybe there was something electrical going on that affected your original sound. Don’t get me wrong, patches can be reproduced, however, it’s not always a one hundred percent guarantee that if you document a patch you’ll be able to reproduce it. That’s where recording and / or sampling the patch comes in very handy. There is something to be said for the ability to call up a preset sound at the press of a button.
There are already several modules being built and on order here at Lower West Side Studio. While there are still lots of spaces available in the 110U rack I expect them to fill up quickly. Expansion will take place first in one portable unit but likely more will follow. There are just too many cool toys out there to try out. We will also be expanding our product offerings here at the Studio so remember to check out our products page and watch for new modules which are often hard to come by but available here.
Finally I should mention the greatest resource for the modular synthesizer aficionado ; Muff Wiggler’s Forum. Sure the name sounds a bit odd for a synthesizer group (read the backstory though, you’ll laugh) but there are a large number of extremely experienced and talented members who are very generous with their knowledge and expertise. You’ll get your questions answered and learn a pile to boot. Give the site a look and remember to keep on wiggling.
For some time now I’ve heard the name Barton Musical Circuits in relation to the DIY modular synthesizer scene. The trouble is that there is so much stuff out there I find myself inundated with a wide variety of vendors, products and technologies that I sometimes hear something then forget about it a short time afterwards having moved on to something else.
Fortunately the other day while surfing I came across a site which I had never found before. It is a vendor called Modular Addict. Intrigued by the name I began to check out their site. Modular Addict officer a substantial number of DIY kits in multiple formats. Under their Multiple / None format I found the Barton line of PCBs. These boards were designed for the Eurorack format, however, it was my intention to modify them for the Moog Unit (MU) / Dotcom format. The boards can operate at 12 or 15 volts which is perfect as Dotcom utilizes + / – 15 volts. The boards even support an MOTM style power connector.
I purchased three types of PCBs; The BMC018 Analog Drum module, the BMC030 Guitar Interface module and the BMC034 Switched Resistor Voltage Controlled Filter module. I figured this was a good place to start.
The boards arrived quickly and were packaged very well. The cost of the boards was very reasonable which is great for something you’ve never tried out before. I looked up some videos on the modules on YouTube and liked the sounds and functions the modules produced.
Documentation for the boards is available for download and is clear and easy to follow for the most part. A bit more detail on the flying wires could be helpful but overall I was able to determine how to wire the jacks from the photos provided.
In order to accommodate the MU format I did have to wire the potentiometers with flying wires rather than using the PCB mounted potentiometers indicated in the documentation. This required an added level of complexity to the build but in reality is wasn’t difficult at all.
One thing I did notice from the photos was that the Ground (Earth) pins on the input / output jacks were not connected. Personally I like my gear to be Grounded so when I wired up my modules I connected the Ground pins together and then to a ground point on the PCB.
I started by building the BMC030 Guitar Interface. The build went quickly and easily and after a couple of hours I was testing the board with my modular. It worked very well allowing me to change the sound of my bass guitar with the filters and other toys in my modular.
For my build, though, I had to design a panel suitable for my Dotcom style cabinet and modules. I chose a 2U panel so that I could use the large knobs associated with MU / Dotcom style builds as well as having the components spaced out comfortably. Once I had a design I used corrugated cardboard and a printout of the panel to create a mock-up. This allowed me to test my layout and ensure things would fit. As it turned out this test showed me that a couple of items needed to be moved a couple of millimetres one way or other. I have made those changes and the panel is now ready to be sent to my silk screen guy to have a screen made.
I did take the liberty of slightly modifying the name of the module from Guitar Interface to Instrument Interface as I plan to plug things other than guitars into it. Just for fun!
Next I moved on to the BMC018 Analog Drum module. This is a cool little module which allows you to create some really cool bass drum and tom sounds. Coupled with some noise you can also create some interesting snare drum sounds.
Once again the build went quickly and smoothly. The module tested out perfectly and I can definitely see adding a few more of these to my modular for some cool electronic drum sounds.
I created a 1U panel for this module which I mocked-up out of cardboard like the first module. This time no adjustments were necessary.
One question that did arise was Barton’s use of 10 Ohm resistors in place of Ferrite Beads to reduce power supply noise. An interesting discussion sprung up from this subject on MuffWiggler’s Forum but in the end, for this first build at least, I decided to stick with the documentation and go with the resistors. So far they seem just fine.
Next up will be the BMC034 Switched Resistor VCF. I have several filters now and I’m very excited to try out another. The different flavours filters give a modular make for a wildly varying sonic experience and I plan to add a large number to my setup.
Once I complete the next build I’ll post a write-up.
So in a nutshell; modules by Barton Musical Circuits, in my opinion, are quite a nice addition to my modular rig. I really like them in the MU format I have modified them for but even as Eurorack modules they are a great add-on. I would also highly recommend them for beginner DIY builders as you get an easy build with some excellent features when you’re done. Oh, and Modular Addict….. excellent place to deal with!
Actually the full name of the module is the Cat Girl Synthesizer CGS01 Sub Oscillator / Harmonic Sequencer…. but that is one heck of a long title.
The CGS01 is a tremendously powerful module whose capabilities are often not completely understood. Truth be told I have yet to fully understand the module’s abilities but I hope to pass on what I do know with this article.
Several CGS01 modules have been built here in the studio. The build is actually quite easy. That is they are easy up to the point it’s time to connect the flying wires. Once you get the trick of where everything goes, though, the modules are a snap to build.
For the CGS01 builds the boards were purchased from Synthcube.com. At the time of this writing Ken Stone, the board designer and manufacturer is no longer selling the boards through his site but his product line is available from Synthcube.com (at very reasonable prices I might add).
Cat Girl modules are among the most unique of the DIY modules out there. First of all they provide a wide and assorted array of features which are not otherwise available in modules by other manufacturers. If the features are available Ken has put interesting spins in his version. Second, CGS modules are frightening to build. When I first came upon the CGS site and read Ken’s FAQ and disclaimer I practically ran away screaming in fright. As a new DIY builder his warnings are very valid. With some research and the excellent support of users on forums such as Muff Wiggler and Electro-Music I was able to successfully build several of his designs.
My first build was the CGS01 Sub Oscillator / Harmonic Sequencer which had some very intriguing features. Rather than acting as a single sub oscillator which would play a note one or two octaves below the main oscillator’s note the CGS01 has a variety of divisions of the primary input note. Further a combination of two inputs could be multiplied and divided then mixed together to produce even more interesting sounds.
In addition to these sound contorting features the CGS01 could alter control voltage inputs such as LFOs. The output of these mashups could then be fed into an oscillator’s 1V/Oct input to create bizarre sequence effects. This is a way cool feature!
The largest number of components on the board are resistors, primarily in the mixer section. A few capacitors and some diodes (and 2 ferrite beads) make up the remainder of the small components. There are 9 integrated circuits used but none of them are particularly expensive or difficult to obtain. In short; building the PCB is a snap.
Wiring the board to the outside world is a bit trickier. There are a number of variations which can be done depending on how large a panel you wish to use, how many potentiometers you want and how complex you want your options.
To keep things within reason and to reduce the footprint of the module I decided to go with Ken’s alternate layout with replaces some potentiometers and a 5 position rotary switch with some toggle switches and a reduced number of pots. I utilized a combination of Ken’s panel layout and one done by Kindredlost from Muff Wiggler to create my panel design which I silk screened onto a Q132 Double Blank panel from Synthesizers.com.
The wiring diagrams on the CGS site are a bit confusing when it comes to wiring up this alternate panel layout so I created my own wiring diagrams for reference.
As suggested in Ken’s documentation I did not tie the flying wires together in my build to prevent cross talk so from the back the module is a bit less tidy than I like but we do what works rather than what is pretty.
Describing the features of the CGS01 doesn’t do the module justice so please watch the following demonstration video for more information.
So to summarize; Great module. Not as scary a build as you might think. Incredible features with a multitude of possibilities. Try one out!