Posted by: Rich Sherkin | May 25, 2016

2015 – The Year In Review

I know 5 months into 2016 is a bit late for a Year In Review article but hey… better late than never.  2015 was a very interesting year to say the least.  Musically a lot of stuff was going on while some… not so much.  So here goes;

Drums / Percussion

Another slow year for the drum kits.  Once you have all the toys you need there isn’t room for much more.  I’m still using my Gretsch Renown Maple kit for studio use and my Pearl Exports (now 35 years old) for live shows.

I’ve played around with heads this year settling on a set of Evans Hydraulic Black for the Gretsch batter heads and continuing to used Remo Pinstripes on the Pearls while using Evans Hydraulic Blues on the resonant heads.  I tried the Hydraulics on the Pearl batter side, however, the sound doesn’t carry well in live situations.  In the studio the Hydraulics work great, especially for recording.

I also scored a great deal on a Pearl hi-hat stand for my gigging kit.  Pawn shops are awesome for gems like this and now I don’t have to tear apart my studio kit hardware when I gig.


Setting Up For A Gig At Piper’s Sports Bar



The Black Evans Heads Look Awesome and Sound Great


2015 was a HUGE year for electronics as I have shifted my focus to DIY gear.  It started with stomp boxes from  These guys have some great clones of really excellent pedals.  I began with a Ross Compressor pedal which, after a bout of using bad solder, worked out really well.

Building electronics was something I did early on in my computer career.  My mentor Dave taught me how to build Apple 80 column clone cards, Z-80 cards and Hayes 1200 bps modem clones.  He was a strict teacher and my soldering skills are really good thanks to him.

Incidentally, if you’re into music DIY and haven’t checked out Small Bear Electronics then you’re missing out on some awesome stuff!

While I enjoy building stomp boxes I really put my skills to use in a new area which came to the studio;  Modular Synthesizers.

Modular Synthesizers

I’ve always been a huge fan of modular synthesizers.  There’s something about all those knobs, plugs and cables that appeals to me.  The sounds they create are astounding and in 2015 I finally got into them big time.

It started early in the year when I built a PAiA 9700 from a kit.  PAiA has been around for a long, long time as a DIY supplier.  I first learned of them back in the ’70s when I saw their Strings ‘n Things keyboard.  PAiA also created the first drum machine which was used in Peter Gabriel’s Games Without Frontiers.  It was only natural that I’d test my skills on one of their modular systems.


The PAiA 9700 – My First Modular Build

I learned to create some incredible sounds with the 9700 and began to study the basis of synthesis itself.  From there I decided to move from the FRAC sized PAiA modules to the larger Moog Unit (MU) size modules which I’ve always liked the look of.

I discovered from where, in October, I purchased my first full size modular system.  I got only a few modules to start but the number of toys I added grew quickly.

IMG_5500 Modular Atop a Moog Sub 37

Following the addition of the “Dotcom” (as they are known in the community) I put my DIY building skills to use adding modules by Oakley Sound Systems.  Today the modular is quite different from the original version but you’ll have to follow the blog and read the 2016 Year In Review to learn about that : )

Incidentally, the PAiA and the Dotcom get along beautifully with some 1/4″ to 1/8″ patch cables.  In 2016 though there have been some format changes to the 9700 which you can read about in the blog.


Not much has been happening in the studio’s keyboard realm with the big focus being on modular synthesizers.  I should note, however, that I did take part in Moog’s Sub 37 Editor program.  Moog had been working on an editor for the Sub 37 synthesizer which has been released in 2016.  It’s quite a nice piece of software which opens up all sorts of possibilities with the synth.

I have to say though that while I really love my Sub 37 many of it’s features are “computerized” for lack of a better word.  Since working with the modulars I find I can accomplish more things more quickly without having to wade through menus and key combinations.


Still working with Reaper and loving it!  They have a great upgrade cycle and terrific support.  I can’t recommend it more highly.


Coming of Age has had a great year performing many live shows at multiple venues.  We’ve done charity events and several private parties all of which seem to really have pleased the crowd.  Our repertoire of classic rock tunes has grown and everyone is having a great time.

Fizzbin is also expanding its musical field adding a number of original tunes to the list of songs we perform.  While we haven’t performed live during 2015 we are preparing an awesome show for the 2016 musical year.  Stay tuned!

So that, in a nutshell, was 2015 for Lower West Side Studio!  Sorry for the late entry but at least I got the info out there.  Keep on Rockin’!!!


Posted by: Rich Sherkin | May 5, 2016

System X ADSR – 5U Version

I’ve recently completed my build of a 5U version of the System X ADSR Envelope Generator by Frequency Central.  I have to admit it was a quick build and not very difficult.  I would definitely recommend it for those interested in getting into modular synthesizer DIY.

I ordered both the PCB and the panel from Frequency Central.  The panel is an MU style panel which sits perfectly in my style cabinet.  The panel design is by Caleb Condit.  The PCB is designed to accept either MOTM or Dotcom style power connectors with +/- 15 volts.

Board quality is quite excellent and very easy to work with.  The board is double layered and very clearly labeled.  The components are quite standard and I was able to build this project with items I already had in inventory.  The only items which I did not have were the potentiometers.  I ordered these from Tayda Electronics as they were not available at my normal component suppliers DigiKey or Mouser.  The parts arrived within a week though so the build wasn’t slowed down too much.

The module is very easy and straightforward to use.  As the name implies there are controls for each Attack, Decay, Sustain and Release.  There is also a switch for selecting Fast or Slow envelopes.  There is a gate input and both normal and inverted outputs.  These features together provide some very cool options for creating interesting effects.


The Completed System X ADSR


Populated PCB With Dotcom Power Connector


Mounted In Cabinet


The following video demonstrates the use of the Fast / Slow switch on the Envelope Generator…

Posted by: Rich Sherkin | April 10, 2016

More PAiA 9700 5U Retrofits

The retrofit of my PAiA 9720 Dual Oscillator / Modulator went really well.  My Moog Unit (MU) style modular synthesizer is growing and the mix of different manufacturer’s brands of components lends to it an eclectic mix of sounds.  While I really love my components I’d like to mix up the sounds produced by my modular by integrating modules from a wide variety of manufacturers.  Having started my modular journey by building a PAiA 9700 I definitely wanted to include it in that mix of modules.

At first I integrated the 9700 with crossover cables.  The were cables with 1/4″ jacks on one end and 1/8″ jacks on the other end.  I got some really cool sounds.  The PAiA modules are grittier for lack of a better word.  They sound sort of like a handful of dirt was thrown into them giving them a more unpredictable sound and feeling.  Perhaps this is because of the use of 5% resistors throughout rather than the more conventional 1%.  It allows for far more drift from the designed specification.  Whatever it is I liked the result and wanted to integrate the PAiA modules more fully with my modular.

As mentioned earlier this conversion began first with the 9720 Dual Oscillator / Modulator.  This conversion brought the number of oscillators in my system up to five.  Having five oscillators in a system has allowed me to produce some damn cool sounds.  I intend to double it before I’m finished.  I was now left with the 9700K MIDI2CV8 converter, the 9710 VCA / Modulator and the 9730 VCF / Modulator.  The nice thing about the PAiA modules is that most include an Attack / Release (AR) or an Attack, Decay, Sustain, Release (ADSR) modulator (or envelope generator).  This flexibility gives the PAiA modules the capabilities of multiple modules.  While the cramming of features into a single module is more of a Eurorack thing it does sometimes come in handy.  The modulators are normalized on the PAiA modules which mean they are tied into portions of the modules circuitry without the need for patch cables.  This normalization, however can be broken through the insertion of a cable into the modulator’s output.

As with the 9720 module the 9710 and 9730 modules only require a slight modification to  support the’s +/- 15 volt power supply.  This modification involves first removing the R1 and R2 resistors and replacing them with straight wire link jumpers.  I just used left over pieces of component clippings for this.  While you can short the resistors by just wiring one end of the resistor to the other there will still be resistance on the circuit as some of the electricity will pass through the resistor so I opted to remove the resistors entirely and add the jumpers.


R1 & R2 (Lower Right) Resistors Replaced With Jumpers

The second step in the power modification involved replacing the 4-pin power connector with a 6-pin Dotcom compatible connector.  The PAiA modules use +15 volts, Ground, Signal Ground and -15 volts.  To add the new connector I simply cut the existing 4-pin connector wires around mid-point and added my 6-pin connector.  Because the Dotcom power supply only has a single ground connection I soldered the Ground and Signal Ground cables together and then linked them to pin 4 (Ground) of the Dotcom connector.  Remember to remove pin # 2 on the connector you use so that it will mate correctly with the Dotcom power supply connector where pin 2 has been filled in for correct orientation.

I should note that I made and tested these power modifications prior to removing the panels from their original FRAC settings.  This way if for some reason the modules failed to function I far less troubleshooting to do than if I had modified everything at once and then tested.  Once I was satisfied that the modules worked with the Dotcom power supply I continued my modifications.

You may have noticed that I didn’t include the 9700K MIDI2CV8 module in the list of modules to which I made this power conversion.  This is because modifying this particular module is significantly different.  While the 9710, 9720 and 9730 modules sit downstream from the 9700K the 9700K itself is connected to the 12VAC wall-wart power supply and supplies the other modules with power.  In order to make the necessary modifications I referred to the Powering the 9700K MIDI2CV8 document provided by PAiA.  This document can be found here.  In a nutshell the modification involves replacing the power connector, rerouting a capacitor, removing the 7805 voltage regulator as the Dotcom supply has its own +5 volt pin required for IC3 (this reduces the power draw by a factor of 10), routing +5 volts to the board and modifying the existing power switch.  This last step is important as the switch cannot simply be removed. The 9700K requires a reset to get things going.  This reset was automatically accomplished with the switch was flipped to activate the power.  I replaced the switch with a momentary pushbutton switch.


Note the Routing of the Yellow (+5) Line from the Power Connector

When transferring the 9700K to a new panel I decided to leave the board’s connectors in their original positions.  This meant drilling out the panel so that the board could simply be mounted in place while allowing access to the MIDI IN, MIDI THRU and DIP switches.  The tricky part was the DIP switch hole which is rectangular rather than round.  For this I drilled out small holes inside the rectangular area and filed it into shape.  My result is not perfect but it works ok for me.  Additionally because the functions of the output jacks varies based on the positions of the switches I opted not to screen the panel but rather refer to a cheat sheet for the functions of the jacks.


Modified PAiA 9700K Mounted In the MU Modular


Speaking of panels…. Rather than pay wild fees to have a single panel screened by a printing company as I did with my 9720 I opted to have a silkscreen produced for each the 9710 and 9730 modules.  This worked out both good and bad.  The screens produced by Metro Graphics in British Columbia were excellent, however, my silkscreening ability is still lacking.  The results I got for the panels were acceptable for my own use but I wouldn’t produce them for sale until I’ve worked out the kinks.  Some things I’ve learned include; keep the screen about 1 – 2 millimetres off the panel itself.  Cover the area to be screened with a layer of paint prior to using the squeegee.  Apply EVEN pressure using both hands when using the squeegee.  Press hard.  In addition the acrylic paint that I’m using may not be ideal and I’m still searching for the best paint for the job.  As you’ll see from the photos the screening isn’t great but as I said… it’ll do for my personal use.

Once the power modifications were done and the panels screened and drilled it was time to  transfer the modules.  The biggest cost for the job was the 1/4″ jacks.  These panels have LOTS of jacks.  The 9730 has sixteen jacks and the 9710 has thirteen.  I used Switchcraft 112AX jacks.  These are 3 connector normally closed jacks.  I could have gotten away with 2 connector jacks for many of the connections but I got a better deal buying the jacks in bulk (for this project and several others I’m currently working on).  Two of the jacks are actually stereo jacks used on the 9710 VCA.  I began by connecting the jack’s ground lugs all together.  The PAiA FRAC modules have some funky methods of connecting the jack grounds to the potentiometers.  By linking all the jack grounds together it became much easier to connect the few pot grounds to the jacks then back to the board.

Once that was done I desoldered the flying wires connecting the 1/8″ jacks to the PCBs for each of the boards.  I should note that I did one complete module at a time rather than complicate things by doing the modules simultaneously.  Then I removed the potentiometers from the FRAC panels and separated the boards and panels.  For all but one connection (the Pan knob on the VCA) the potentiometer wires interconnecting one another did not have to be cut.  Only one or two ground wires linking the pots to the 1/8″ jacks had to be cut and these were easily reconnected to the new 1/4″ jacks as the jack grounds were all linked together.

I used the PAiA Illustration Supplement for each module to guide the re-wiring process.  I first connected the required resistors, capacitors and bridge wires to the necessary jacks before attempting to wire the flying wires to the panels.  This made soldering things in place much easier.  I then mounted the potentiometers to ensure everything fit into place nicely.  The next step was to connect and pot grounds to the jacks to ensure everything was grounded correctly.  Finally, following the supplements, I connected the flying wires to their respective sockets.  Once again, as with the 9720 VCO, the wire lengths were sufficiently long that they reached their target jacks without extension or replacement.


9710 VCA Refitted

I did have to remove each module’s LED and add some flying wires to the PCB so the LEDs could be relocated to accommodate my panel design.  Just for kicks I used blue LEDs for the PAiA modules making it easy to locate them in the dark.

Once done each panel was tested using a bench power supply before connection to the modular’s Dotcom QPS1.  If I made a mistake the bench supply would take the hit rather than my production machine.  Fortunately each module worked perfectly and I installed them into the modular after calibration.

So now my modular has the added bonus of some PAiA modules plus I now have 2 MIDI to CV modules allowing me to run my keyboard to some oscillators and an external iPad based sequencer (I still don’t have a sequencer module) to other oscillators.  I’m very pleased with the result!


5U 9730 VCF / Modulator


9710 VCA – Note the Right Side – Apply EVEN pressure when Screening






Posted by: Rich Sherkin | February 21, 2016

PAiA 9720 5U Retrofit

Last year I began my adventure into the world of modular synthesizers by building a PAiA 9700 modular synthesizer.  The 9700 is a DIY kit consisting of a MIDI to Control Voltage Converter, Voltage Controlled Oscillator / Modulator, Voltage Controlled Filter and Voltage Controlled Amplifier.  These are the basic building blocks of synthesizers whether  modular or all-in-one units.


9700 Connected To Roland A-300 Pro MIDI Controller

There are several different size formats for modular synthesizers;

Eurorack is by far the most popular.  The modules are 5.06″ tall, utilize 1/8″ connector jacks (like iPhone headphones), are crammed with features and have very colourful and busy faceplates.  They also run on +/-12 volt power supplies.

Moog Unit modules or MU (or 5U) are based on the early Moog Modular synthesizers.  The modules are 8.75″ tall with varying widths.  MU modules use 1/4″ interface jacks (like guitar cords).  They tend to have a more uniform and conservative appearance as well as larger controls with more space between them.  Most modules have one or two specific features.  MU systems generally operate at +/-15 volts.

The PAiA modules are in FRAC format.  These modules are 5.25″ tall and like Eurorack utilize 1/8″ jacks while cramming lots of features and small controls onto each module.  These modules are designed for +/-18 volts but can operate at +/-15 volts with slight modification.

This is a very basic outline of the various modular formats.  For more information you can follow this link.

Each of these different formats can work together providing you use the correct cable types.  Each format, however, must have its own appropriate power supply.

Personally I prefer the Moog Unit format.  I like the clear, clean, consistent design of the panels.  I find the larger plugs and knobs easier to handle and I find their overall appearance quite impressive.  Late last year I began to build a new modular synthesizer by  In addition to the Dotcom system (as they have come to be known) I also build DIY modules by Oakley Sound Systems, Yusynth, Cat Girl Synth, Moogah and others.  These modules provide the basis for a very powerful sound sculpting platform.


I wanted to make my existing PAiA system part of that platform.  At first I tested the two systems together by cross patching them.   The two modulars work well together but what I really wanted was full integration.  While surfing the web I ran across a modular builder at  He had created custom made panels for his PAiA 9700 modules and remounted the PAiA electronics into these panels as well as replacing the 1/8″ jacks with 1/4″ jacks.  I got in touch with him and he outlined some of the things he had done as well as providing me with his panel graphic.  Thanks for all your help Jeff!

The first module I wanted to convert was the 9720 VCO.  This module is actually two Oscillators and an Attack / Release Modulator.  I made some modifications to the graphic and had a panel screened.  I used a Q133 quad panel.  This ensured a consistent look for the modular and a proper size fit.

The next step was to prepare the 9720 to accept +/- 15 volts as output by the Dotcom’s power supply.  This involved removing R1 and R2 on the 9720 and replacing the resistors with a piece of wire.  You can also connect wires between the resistor points to short them out, however, leaving the resistors in place means that there will still be resistance along the electrical path.  Thanks to Scott at PAiA for clarifying this info.  Finally I replaced the power connector with a Dotcom compatible connector.  Both ground lines from the 9720 must be connected together then connected to the Dotcom’s single ground line.  With this done and tested the time had come to swap panels and jacks.


9720 Modified For +/-15 (Note: Power Connector And Blue & White Wires In Upper Left)



New Panel (Prior To Hole Drilling) Next To Existing 9720


Disassembly didn’t take very long.  Fortunately the potentiometers did not require having their flying wires desoldered which saved quite a bit of time.  Some of the pot to pot connections had to be severed due to length constraints then reconnected once moved.

Because the jacks were all being replaced I desoldered all the flying wires connected to each 1/8″ jack.

Following PAiA’s build document for reference I first added the new 1/4″ jacks, connected the ground leads and then (after repositioning the potentiometers) began connecting the specialty connections such as the capacitors, resistors and cross connections between jacks.  I then ensured that all the connections to the potentiometers were back in place.  Finally I soldered the flying wires back to the new 1/4″ jacks.


Rewired 9720 Panel

With the system rewired I first tested the module on my bench power supply.  I highly recommend a separate bench-test power supply to anyone doing DIY modules.  In case something has gone terribly wrong the bench supply will short out rather than your modular power supply and any of your modules.  Personally I think it’s worth the extra expense.

With the module tested and working it was time to install it in my modular.


New Panel Integrated Into Modular

My inventory of 25mm knobs was low but I plan to replace all the knobs so that they match the rest of my modular.  The larger knobs are also much easier to manipulate than the tiny PAiA knobs.


S.W.A.N. – Synthesizer With A Name

I’ve already designed a graphic for the PAiA 9710 VCA which is my next conversion project.  Before that though I have a few new modules to build.


5U design for 9710 VCA

EDIT:  VCO with nice chunky 25mm knobs



Posted by: Rich Sherkin | January 23, 2016

Yusynth Minimoog VCF

So far 2016 has been a great year for DIY modules at Lower West Side Studio.  Following the successful build of a Moogah SEM VCF I built a module that I’ve wanted since the moment I saw it; the Minimoog VCF clone produced by Yusynth.

There is nothing like the sound of a Minimoog and that is largely because of its transistor ladder filter.  Yusynth created a circuit based on the original and, like many of his other modules, he has published details on how you can create your own PCBs and build your own modules from scratch.  Unfortunately he does not sell any of his products.

Fortunately for me I didn’t have to etch my own PCB. came to my rescue by having some of these PCBs in stock!


The PCB quality was quite excellent.  Very well made and very clearly labeled.  The build documentation for the board, however, is pretty much non-existent.  Yusynth has a page on their site detailing the Bill of Materials along with some very detailed images of the board, component layout, off-board wiring and of course the schematics.  If you’re hoping for a step-by-step instruction manual though, Yusynth boards are not for you.  They are more of an intermediate to advanced build.  Yves detailed diagrams are excellent though and I had no problem putting the board together.


While the Minimoog filter is not particularly complicated there are a couple of things to note; there are six BC547 transistors required and these must be matched pairs.  In addition the four 47nF capacitors must be matched to within 1%.  To match the transistors I built a simple breadboard transistor matching circuit.  I used a circuit based on Ian Fritz’s design.

After selecting the correct pairs of transistors and group of capacitors my build went quickly and smoothly.

Once I completed the build I came to the part of DIY synth module building I dread… the panel.  Yusynth provides images for producing silkscreens of the panel, however, presently my silkscreening process is not up to snuff.  This was horrible.  I had a completed, tested working module but no panel to mount it in.


Then I discovered Free State FX.  They are builders in the US who provide panels for a number of Yusynth modules including the Minimoog Filter.  While the Canadian Dollar is very weak as of this writing the Free State FX panel was still significantly less expensive then the panels produced for me by a local screening company.  I received the panel very quickly and the quality was really good.  I should note for all those who do not wish to build their own Minimoog Filter module that Free State FX produces a built version for sale.


Mounting the board into the panel went very smoothly and it was soon connected to my modular for testing.  It works great!  I still have to run the calibration procedure to ensure it tracks volts per octave correctly.  Additionally frequency and emphasis adjustments have to be calibrated.  At this point though I’m extremely happy with the module.

One very nice feature about the Yusynth modules is that they run on 15 volts and utilize a power connector.  This makes for quick and easy installation in my modular synthesizer.  One thing I should stress is the importance of a bench power supply for testing modules before installation into the main system.  It costs a bit extra to have a power supply that only comes out for builds but in the event of a build error it can prevent your modular’s power supply and modules from being damaged.  I use a QPS2 desktop power supply for this purpose.

I’m very excited to have this module as part of my modular synthesizer.  I plan to add several more Yusynth modules to my rig in the near future!  Thanks to Yves Usson for the excellent design and to for stocking the part.

Stay tuned for sound samples…

Posted by: Rich Sherkin | January 22, 2016

Moogah SEM VCF

I recently completed a build of an Oberheim Synthesizer Expansion Module Voltage Controlled Filter work-alike produced by Moogah (Jeff Farr).  I picked up the panel plus PCB package from

I’ve always been a fan of Oberheim gear from way back in the ’70s.  Geddy Lee from Rush was probably my first experience hearing an Oberheim (at least I knew it was an Oberheim that I was hearing).  In fact Geddy had a Moogerheim mashup.  One very cool feature of the Oberheim’s were their filters which, as I began to understand the workings of filters more and more as my modular synth experience grew, I decided I wanted to add to my modular rig.


Geddy and his Moogerheim

A very cool feature about the Moogah SEM VCF was that Jeff Farr got Tom Oberheim’s blessing for his design of Tom’s circuit.  The VCF is a 2-pole filter which runs at either 15 or 12 volts (based on a couple of resistors).  There is no V/Oct control voltage so like the original it will only track a few octaves.  There is also no control voltage for the resonance (like the original), however, there is an option to build this in.  The PCB includes locations for the appropriate circuitry, however, the pre-made panels do not include a location for the required potentiometer and input jack.

Wanting my VCF to be as close to the original as possible I opted for the build without the voltage controlled resonance.  There are presently two panel formats available for purchase;  Eurorack and Dotcom/MU.  Because my modular is Dotcom based I opted for the Dotcom panel with the 15 volt power option., the online supplier of the board and PCB, has a nice panel designed by Caleb Condit.  The panel is made from anodized aluminum and illustrated using the metalphoto process.  It is manufactured in the US.  While I really liked being able to purchase the panel with the board both the design and illustration left me a bit flat.  The panel is painted with a flat black paint which tends to show fingerprints more than its Dotcom counterparts.  The white printing is more off-white and significantly less bright than silkscreened panels.  The design, while functional has more of a Eurorack disco feel to it.  I like my potentiometers labeled with numbers rather than cryptic shapes.  Please note that these are only my personal preference.  The panel is well made and just receiving a panel with the PCB was a blessing.  There’s nothing worse than having a circuit built with no panel to install it into.


The finished SEM VCF (Centre) among Dotcom panels

The SEM VCF is by no means my first, second or even fifth build.  I am not a skilled electrical engineer by any means although I do have relatively good soldering skills.  That said I must point out that this project is definitely NOT FOR BEGINNERS!

Step 1 in the documentation reads “The PCB requires a trace cut to address a design issue”.  YIKES!  That was a new one for me and definitely a bit scary.  The documentation, however, clearly shows where the two traces must be cut.  It also suggests to use a continuity tester to ensure the traces are cut.  I cannot recommend this step enough.  Just because it looks cut doesn’t mean the connection has actually been severed.

Cutting traces often involves adding jumper wires to reroute the flow of those cut traces.  This board is no exception and two jumpers are added later on in the build at step 22 of the manual.  This is a bit of a tight solder to points on the op-amps as they are close to some SMT caps.

Speaking of SMT or Surface Mount Technology caps – these suckers are SMALL.  VERY SMALL!  Normally SMT components are installed by machines.  They allow us to have very tiny devices like cell phones.  Soldering them by hand is a difficult process but not impossible.  It takes patience and a steady hand.  As my first attempt I can say that while not perfect, I did ok.  There is a handy video from Colin’s Lab showing how to solder SMT devices.  In addition – get smaller tweezers than the ones shown below!


Next to my index finger and tweezers – this thing is small!


The PCB quality of the the SEM VCF is quite good, however, unlike several other boards I’ve used the components aren’t marked by their reference numbers (e.g. R1, R2, C15, etc…).  They are, however, marked with their component values.  This makes it a bit trickier locating their positions especially as some of the labels are obscured by the through-holes drilled into the board.  Several of the labels are marked with dollar signs ($) to indicate that they are required for building the version of the board which includes the resonance control voltage.  Others are marked with asterisks (*) to indicate they are to be excluded for the CV resonance version.  Overall though I found it easy to locate the component spots and to populate the board.


The documentation for the project is quite good with one exception;  it is only for the Eurorack build.  While there is reference to which resistors to install depending on your power supply’s voltage, 12 or 15 volts (step 8) there is no warning about soldering the potentiometers to the board for the Eurorack panel (step 18).  I didn’t catch this at first and had to desolder my potentiometers.  What a freaking nightmare.  All went well though and I attached flying wires to the three potentiometer locations for the pots.  While a separate documentation is not necessary for the 5U build of this project it would be helpful if the author could mention the slight differences in the builds for the reader.


Pots soldered on before removal


After desoldering replaced with flying wires

Obtaining parts for the build was not too tough, however, there are three 2N4302 transistors which are discontinued and a bit tricky to find.  I was able to find work-alike versions of these transistors from Small Bear Electronics.  Incidentally, Small Bear is an AWESOME source for components for many DIY projects!

Another VERY important note is that if you are using the provided spreadsheet Bill Of Materials there is an error on row 25.  The Poly Cap listed is 150nF (nano-farad).  It should be 150uF (micro-farad).  Big difference!  This is corrected in the Bill Of Materials contained in the build document, however, not on the spreadsheet.

As I mentioned earlier, having the panel to install the board onto immediately after it was done was a tremendous advantage.  Once completed I tested the unit with my bench power supply.  I cannot stress enough the need for a bench power supply.  If a mistake was made on the board I would much rather blow up a bench supply then the power supply in my modular and also risk taking some modules with it.  I use a QPS2 desktop power supply.  I’ve also modified one of the power connectors to support a MOTM/Oakley style connector.  This allows me to test both Dotcom and MOTM/Oakley modules with no muss nor fuss.  The VCF utilizes an MOTM/Oakley style power connector.  Once tested I built MOTM to Dotcom connector convertor and installed the unit in my modular.


Setup and ready for testing

So there you have it!  A very cool module built in about two days.








Posted by: Rich Sherkin | December 5, 2015 Meet Oakley

The world of modular synthesis is incredibly fascinating.  There are so many different modules from so many different vendors which allow one to mix, match and manipulate sounds and signals in unlimited unique ways.  Each modular synthesizer can be an individual design limited only by the builder’s imagination, capabilities and of course…. cash ; )

For me, building modules from scratch is as much fun as buying them as complete units.  Fortunately the modular world has divided itself into various form factors permitting the artist to chose which size, Frac, Eurorack, MU (Moog Unit) and MOTM, they wish to pursue.  Many DIY vendors provide boards which can be installed in multiple sizes.  Personally I prefer the Moog Unit used by Moog and

One vendor who’s modules I quite like is Oakley Sound Systems in the UK. Not only does Oakley provide top quality PCBs for a variety of very cool modules along with excellent documentation and support, they also provide graphics which can be submitted to Front Panel Express for quick and (reasonably) cost effective panel creation.  As I discovered though, the panel graphics are suited for MOTM rather than Dotcom panel sizes.  While the panels are 8.75″ tall the MOTM panels are 1.75″ wide versus the the 2.125″ for Dotcom and Moog.  The upshot of this is that a gap will exist between modules when they are installed in a cabinet along with other Dotcom modules.  While blank space fillers can be used to bridge the gaps I was looking for a more visually appealing solution.

I decided that the best way to ensure the panels adhered to the Dotcom specification I purchased several blank panels from After looking at various options for labeling the panels including stick on labels and engraving, neither of which were very appealing I came across a synth-builder named Jeff from  He had built and modified a variety of modules which he then fitted into Dotcom panels which he silkscreened the graphics onto.  The result was exactly what I was looking for!

I created a template of the Dotcom panel from the specifications so kindly provided by Roger of  For this I used an old copy of Visio I had lying around.  Once I had the template I overlaid a JPG image of the Oakley graphics which I output from the Front Panel Design program.  Using this image on its own layer as a template I created new graphics using the fonts recommended by Roger for the Dotcom modules.  Now things started to look the same.

Placement of the drill holes was the critical factor.  Because Oakley modules use special mounts on the potentiometers to fasten the PCB to the panel (if you choose to build that way) the holes must be placed in exactly the correct locations.  Further, Oakley provides PCBs for easy wiring of the I/O sockets.  Like the potentiometers the user can opt to choose their own method of wiring them to the panel but I opted for the PCBs (the SOCK4 and SOCK8 panels).  Once again the holes must be perfectly aligned or the sockets will not fit correctly.

For my first run I found a local printing company who was up to the task of screening my metal panels.  While they did a very good job at the screening process the cost was very high.  So high in fact that I could have purchased all the screening gear I required and done it myself with screens left over to do more panels.  Well, everything costs the most during the prototype phase so I chalked it up to that.  In any case, the panels look good and despite a minor numbering error that I overlooked after they re-did my artwork the modules look great.

So now I’m in the process of obtaining the gear to do it myself.  As I plan to build a few modules and sell them I figure it will drive my build cost way down.

For now though I’m happy that the Oakley modules that I’ve built fit perfectly in my Dotcom cabinet!



Posted by: Rich Sherkin | November 16, 2015

Lower West Side Studio Loses A Dear Friend

I am deeply saddened to write that our beloved friend and family member Baxter has passed away.  Baxter was our Doberman Pinscher.  He was not only a part of our family but also a part of our studio.

Baxter was our third Dobe as my wife, son and I love the breed.  Unfortunately Dobes are known as The Heartbreak Breed because they have a ten year life expectancy.  This is not uncommon in larger breed dogs.  Contrary to their imposing appearance and all the negative press they were given throughout the 1970s Doberman Pinschers are a gentle, highly intelligent and loving breed.  Our first two Dobes, Zaphod and Tricia grew up with our son who was four years old when we first got them. Actually Zaphod came first and Tricia joined the family five years later.  After Tricia’s passing in 2005 we visited a wonderful Doberman breeder in Schomberg, Ontario named Angela.  We learned a great deal of the importance of a proper breeding facility through Z and T who came from much lesser quality breeders.  Nonetheless we loved them so much.

Baxter was from Angela’s N Litter and was subsequently given the show name Di Ravallese’s National Treasure.  He was a wonderful boy so full of energy and intelligence.  We socialized him early and well introducing him to many adults, children and other dogs.  Baxter was a show dog in the early years and went on to become a Canadian Kennel Club Champion in 2007.

Di Ravallese's National Treasure

Baxter was a gentle soul who loved everyone and everything.  At our old home in King City Baxter would often lie on the grass in the backyard and watch birds.  Never before had we seen a dog who would lie four or five feet away from birds on the grass watching them rather than barking and chasing them.  He was a very special guy.

When we moved to our new home and I rekindled my passion for making music Baxter was right there with me.  At first when I set up our studio Baxter would come into the room while I was drumming and ‘sing’ along to the music.  He had a preference for Led Zeppelin.  Don’t ask me why… he just did.  After seeing several of my friends come by the house and play their guitars and sing Baxter became interested in the spring door stoppers behind each door in the house.  He would twang them with his paws repeatedly and bark along to the twanging.  It was his version of playing guitar and singing.  He did it so often and to so many door stoppers that we had to remove them and replace them with the type that mount high up on the hinges.  You see he was accidentally damaging the hardwood baseboards and hurting his paws.

Not wanting to stifle his musical ambitions I built him a synthesizer which we dubbed The Baxtersizer.  It consisted of an inverted plastic dog bowl mounted on a sheet of wood as well as a block of wood with a spring door stopper mounted as well.  Inside the bowl was a drum trigger.  The contraption was connected via an XLR cable to either a Roland PAD-80 drum trigger or directly to a DAW running a drum trigger VST.  With this setup the Baxtersizer could trigger a variety of sounds for Baxter to play.  I would start an arpeggio on my synthesizer and the Baxter would play his ‘lead’ and bark his vocals along to the beat. Upon seeing Baxter do this my friend and Fizzbin bandmate John pointed something spooky out;  he’s doing it on tempo!

Since building his synth each time I keyed the first note on my synthesizer Baxter would come running into the studio wanting to play his Baxtersizer.  Most times I let him play for fifteen minutes before beginning my own session.  After all… it gave his pleasure and exercised his mind and body.  Plus it was pretty cool.

Almost two years ago when the Classic Rock band I play in, Coming of Age, began to play here Baxter was right there with us.  I would tell him ahead of time that his boys were coming to play music for him and promptly at 5:30 on rehearsal nights he’d be standing by the front door waiting for the guys to show up so he could greet them and determine which one of them brought the pizza.  Our family spoiled Bax a bit and I would feed him some of whatever I was eating in the studio with the guys.  Bax would then survey the situation and lay outside the glass studio doors so he could watch and listen without it being too loud for his sensitive ears.  Last week we began working on an acoustic version of our set and Bax lay in the middle of the circle of musicians digging the mellow tunes.  He was such a good boy and music lover.

Early last month Bax began to really slow down and show signs of some type of illness.  We suspected it was DCM, a heart condition he had been diagnosed with a few years ago.  It was DCM but in addition to that Baxter also had Lymphoma.  We put him on a series of medication but did not opt to have any Chemotherapy or invasive Cancer treatments done.  At almost ten and a half it would have been cruel to end his life with that kind of suffering.

Earlier this year Baxter’s daughter Fiji was supposed to have a litter.  Baxter was bred twice and has thirteen children.  Unfortunately that litter was never conceived but in early September Fiji did have a litter of fine puppies.  Baxter’s grandchildren.  Nine days ago we brought home Baxter’s grandson Bogey.  Despite his poor health Baxter played with Bogey and taught him many things including (thankfully) where puppies go to the bathroom.  Bogey potty-trained in just two days.  The two of them enjoyed each other’s company lightly playing and going for short walks.  By the end that was all Baxter could manage.

When Bax’s condition declined rapidly starting last Friday night we called the Vet to our home to give Baxter peace and relief.  She did just that and we are so thankful for her help despite the massive sorrow we now feel.  Baxter’s many friends have sent kind words and condolences and we are grateful to them for their comfort in our time of grief.

Now with our fond and wonderful memories of our very special and unique friend we will raise Baxter’s grandson Bogey with all the love, attention and care that we gave to Baxter.  That’s what he would have wanted.  We miss you so much Bax and will never forget your kind nature and wonderful personality.

Baxter Enjoying A Sunny Afternoon In Happier Times

Baxter Enjoying A Sunny Afternoon In Happier Times

Posted by: Rich Sherkin | November 3, 2015

Modular in the Lower West Side with

When I was a young boy back in the ’70s I happened to catch a late-night showing of Brian De Palma’s campy horror movie The Phantom of The Paradise.  In the movie disfigured composer Winslow Leach is taken in by his tormentor, renowned record producer Swan, and tricked into completing the musical score for a rock opera.  Leach looses his voice in an accident and Swan hooks him up to a vast array of synthesizers to allow him to sing so that he might complete his work.  This synthesizer turned out to be the legendary TONTO synthesizer.  TONTO is a synthesizer built by Malcolm Cecil and Robert Margouleff and stands for The Original New Timbral Orchestra.

Phantom and TONTO

At the time I knew none of the synthesizer’s history.  I only knew that one day I wanted a musical machine with knobs, dial and cables just like it!

At the time I was about 12 years old and already playing drums.  Still, I enjoyed visiting music stores and playing around with the synthesizers of the day.  These were legendary synthesizers by Moog, Korg, Arp and others.  I had taken piano for several years and could make some very cool sounds with them.  One day, I decided, I would have a room filled with synthesizers the likes of the machine I saw The Phantom playing.

Flash forward 39 years…


After a long career in Information Technology (so long that it was called Data Processing when I began) I built a home studio and populated it with instruments I had only dreamed of owning as a youth.  While I have a collection of percussion and stringed instruments it is my keyboards that I think I love the most.  If you’ve followed this site you may have read about the Yamaha DX-7 II, Yamaha Motif XF6 and even the Moog Sub 37 I’ve added to my collection over the past few years.  All these machines are wonderful and have their own unique character.  The Moog in particular with its meaty analog sound.  Still, none of them have the wild look and feel of a modular synthesizer.  More importantly none of them have the limitless patchability offered by modular synthesizers.

Earlier this year I began my venture into the modular world by building a PAiA 9700 modular synthesizer.  The building experience was quite awesome and being rewarded with a very cool musical instrument at the end of my journey was wonderful!  The 9700 is a great entry level synth for learning the ropes of modulars and it has taught me many things.  I’m very happy with it.

Wanting to move to the next level I had to decide whether I wanted to expand the PAiA with more modules or veer off in a different direction.  The PAiA uses a form factor known as Frac which is 4U or 5.25″ tall.  The more popular EuroRack format is a bit smaller at about 3U or 5″.  Still my heart yearned for the wall of synthesizers that I had seen as a kid.  I learned that those modules were of the larger format known as Moog Units or MU.  This was because many of the modules in TONTO were made by Moog.  MU is 5U or 8.75″ tall.  Perfect!

I then began research into MU form factor modular manufacturers.  While I would love a Moog Modular they are extremely expensive.  I discovered that a company called was making MU sized modules and they were doing it in a manner which closely replicated the actual Moog components.  I also discovered that (or DotCom) synthesizers were very highly regarded and widely used by professional and non-professional modular synth players.

It was at that point I decided to make the DotCom synthesizer the foundation of my modular synthesizer project.  The modules and cabinetry are all hand made in Texas and the quality is absolutely incredible!  Using their free application SynthInvent I was able to piece together a starter system which would get me on my way to building the wall of synths I desired.  I started with a basic 22U wide oak cabinet.  After choosing a power supply I then added 2 Q106 Oscillators, 2 Q109 Envelope Generators, a Q107 Voltage Controlled State Variable Filter and a Q108 Voltage Controlled Amplifier.  These are the core elements which make up most analog synthesizers, modular or otherwise.  I also added a Q174 MIDI Interface to connect my keyboard and the Q175 MIDI Interface Aid.  This latter provides extra MIDI interfaces, an arpeggiator and a glide feature.  To round off the initial system I included a Q110 Noise Source and a Q124 Multiples module.  The Q124 is like a one-to-many splitter which allows one signal to reach multiple modules.  I filled in the blank spaces in the panel with a Q134 Octal Blank panel.  This wasn’t the best choice for a space filler as I learned later but not a fatal mistake.

The Modular atop the Moog Sub 37

The Modular atop the Moog Sub 37

This, at last, was the start of my journey into the large-format modular world!  Since my initial purchase I added the Q115 Spring Reverb.  Because it is an analog reverb the unit incorporates a reverb tank with 3 springs.  The tank mounts inside the case and it was very easy to do.

I’ve also started building some modules by Oakley Sound Systems in the UK.  These are DIY modules and they are very good quality.  The only problem I encountered (aside from a glitch or two due to errors on my part) are that the supplied panel drawings are MOTM style and don’t quite fit into the DotCom cabinet.  I am presently working on a work-around which I will post about later on.  The modules I am have built are the 4014 Ring Modulator and the Dual LFO.

The sounds I get from the DotCom synth are amazing.  The Oscillators provide a full, rich tone with deep lows that rival even my Sub 37.  The VCF is very flexible and really makes the sound incredible.  I am experimenting with the various optional patches I can make using the gear that I have.

I am also interfacing the PAiA 9700 with the DotCom and vice versa.  I have got sounds out of the PAiA that I never thought possible and altering the DotCom’s control voltages with output from the 9700 has yielded some amazing results.  I intend to expand both synthesizers and see what I can come up with.

Modular synthesizers are very different from standard synths which feature presets.  Once I get a sound on my Sub 37 I can store it, move on and then recall the exact same sound I originally programmed.  With the modulars even if I set the patch cables the same and the knobs in the same positions the sound produced is not always exactly the same as what I first patched.  Close and sometimes the same but not always.  For this reason I have begun to record samples of the patches I make which I can then either program into my Yamaha Motif XF6 or incorporate into tracks in my DAW.  I can even alter them in the DAW and then store them as samples.  The possibilities are limitless.

I also plan to get the Q118 Instrument Interface so I can patch in guitar, bass, vocal and other sounds which I can then mash up with the modular’s components.  Anything imaginable is possible with these units.  It’s a truly amazing technology for something that was invented back in the 1960s.  The fact that we still use it today says something about its longevity.

I only wish I bought more patch cords : )

Posted by: Rich Sherkin | October 19, 2015

Oakley In The Lower West Side

Recap;  Earlier this year I built a PAiA 9700 modular synthesizer.  What a fantastic toy.  Even with only a few modules I am able to generate some very cool sounds.  Further, the 9700 interfaces well to my Moog Sub 37’s Control Voltage (CV) jacks allowing it to modulate features of the Sub 37 to create even cooler sounds.  I’ve also played with outputting audio from the 9700 to be modulated and twisted by the Sub 37.  This has yielded some very interesting results.  These will be out soon on a recording my band Fizzbin will be releasing soon on SoundCloud.

Modular synthesis has always fascinated me as have synthesizers in general.  As a youngster I first saw a massive modular in the movie The Phantom of The Paradise.  That modular was Tonto and although it wasn’t showcased in the movie I was intrigued by all the panels with their knobs, switches and ports.

After building the 9700 I began to seriously look at the modular synthesizer scene.  I discovered that for the most part the scene was common across the board except for formats.  I’m not going to get into East Coast versus West Coast philosophy here although that is another variation of the formats.  The size of the panels themselves is the big differentiating factor.  Power supplies are another main difference.  If you’re interested in learning details about modular synthesizers I highly recommend the documentary I Dream of Wires.  It’s available on Netflix.

The 9700 and other PAiA modules use a size called Frac (5.25″ tall or 3U).  One of the most popular sizes of modules now is the EuroRack (5.06″ tall or close to 3U).  These modules are easily mounted in portable cases making them ideal for schlepping around to live performances without too much effort.  The modules that most caught my attention, however, are sized in MU or  Moog Units (8.75″ or 5U).

While MU modulars can definitely be made portable they are more often seen in studio based cabinets.  The MU factor gives the modules more space on which to mount nice big knobs which are easily manipulated.  They also permit more clear labels and less cramming of controls.  These are, of course, my personal opinions and the primary reason I like the format.

Having said all this I set out in search for an MU style platform from which to launch my modular synthesizer project.  In a perfect world I’d purchase a Moog Modular system, however, it’s 5 figures just to get into that game so I searched for an alternative.  That’s when I discovered  DotCom (as they are known) systems are designed with a very Moogy flavour not only in looks but also in sound.  They are made in Texas by hand.  Many DotCom modules are available and you can mix, max and expand as you require.  My initial system consists of a 22U rack (width), power components, MIDI to CV interface,  2 oscillators, 2 envelope generates, a noise source, multi-port patch panel, voltage controlled amplifier, voltage controlled filter and reverb.  A nice start.

So what about this Oakley business?!?!

I still love the DIY aspect of synthesizers and because of this I was looking for a way to build my own modules for use in my new DotCom unit.  I should mention that as I write this my DotCom synth is in transit and I have not even seen it yet.  Oakley Sound Systems is a manufacturer in the UK which produces a wide variety of PCBs which you can build yourself.  They not only provide the boards and select components for them but also excellent documentation and design specifications for panels.  These panels are available in a variety of sizes so the same board may be used in different format synthesizers.  Not only are the boards very reasonably priced they are excellent quality and very well supported.

I started off by purchasing two boards;  The 4014 Ring Modulator and the Dual LFO board.  I have completed the 4014 at this time.  This board is based on the ARP4014 Ring Modular used in the ARP 2500 and 2600 modular synthesizers.  These modulars were ground-breaking in the 1970s and I felt that using some of their components in my modular would make for some awesome sounds.

The build went very smoothly because as I mentioned, the documentation is excellent!  It would have  been finished a day early if I would have paid closer attention to my parts order and not ordered an incorrect part.  No harm done though.  I can’t plug the unit in to test until I receive a bench power supply that I ordered from  I don’t intend to plug any home-built modules into the actual synthesizer’s power supply until I’ve confirmed they’re working ok in a closed environment.  That’s a holdover method I used as a software developer and network engineer for 30 years and it’s as wise today as it was way back when.

More to come when I build the LFO and especially when my DotCom unit arrives.  Until then, here are some pictures of the 4014 Ring Modulator build…

Beautifully laid out board with easy to read labels

Beautifully laid out board with easy to read labels – Note how the labels are beside the components so you can still read them once the components are installed.  Makes for easy debugging!

Almost populated - Saving the ICs for last

Almost populated – Saving the ICs for last – The board supports multiple power options for use in different manufacturer’s modulars.

Completed the soldering - Time to mount to the panel

Completed the soldering – Time to mount to the panel

Mounted to the front panel

Mounted to the front panel

Completed 4014 Ring Modulator

Completed RM-4014 Ring Modulator

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