Saturday, January 7, 2017

The Unofficial Nick Batt Eurorack Synth - A Celebration of PWM

I was sitting here, with a tremendous headache, and I didn't want to work on my gear. I didn't want to waste time either so I wondered, what would Nick Batt do? I pondered that thought for a moment when it came to me, Nick would design the ultimate PWM synth on So I lit a few candles, took some asprin, put on some Andy Stott at a very low volume, and got to it.

Before channeling Nick's thoughts I established a few ground rules.

1. The synth should use no more than 3 rows at 104hp in width. After all, Nick needs to be able to carry it around without hitting the gym.
2. The synth needed at least twice as many VCOs as a Dewanatron. Maybe Trent Reznor would like this synth too one if I put a ribbon controller on it.
3. This synth needed Maths, because according to, everyone needs Maths.
4. This synth needed to be laid out in a way that was easy to patch and all components needed maximum utility for their size.
4. This synth should have stereo output as we can't have all that PWM goodness hiding inside of a mono track.
5. This synth needed to have some special analog phasing to emphasis PWM and the VCF's sing songy resonance.
6. You can never have too many VCAs

Here is what I came up with in about 10 minutes. What can I add to this synth to get the attention of my two heroes, Nick Batt and Trent Reznor?

Monday, January 2, 2017

Expanding the Mother 32 - Part 4 - Adding a 2nd VCF

The filter in the Mother 32 is a sweet sounding VCF that does that wonderful Moog'y low pass thing so well. The transistor ladder VCF has a sophisticated richness and syrup like sound that you just don't get with any other design. But when you roll up the resonance the bass from the VCO just drops away. Also, there is no useful high pass to speak of. I'm not saying the Mother 32's VCF is useless, it's just not as flexible as I would like. I stumbled upon a great deal on an Intellijel µVCF as I was searching for the right filter to pair with the Mother 32. The little 6hp Intellijel filter doesn't have the most character of any VCF I've heard, in fact it's sort of a chameleon, but it's extremely flexible and has many uses.

Here are 8 reasons why you should consider the µVCF for your Mother 32 rig

1. µVCF can pull off some nice format sounds.

2.  The µVCF can self oscillate and produces a clean sine wave that tracks well. Sine waves are incredibly useful for FM synthesis. Just let the  µVCF's LPF output find it's way to the Linear FM input on the Mother 32 and have at it. To ensure accurate tracking, you'll need to buffer the KB output on the Mother 32 before patching it to the  µVCF, as you would most VCOs.

3. The µVCF doesn't loose bass output when you crank the resonance and sweep the cutoff down. This is helpful for patching big bass sounds and thunderous drones.

4. The µVCF has excellent BPF and HPF outputs that work correctly, unlike the Mother 32's HPF.

5. The  µVCF  is small at 6hp and laid out for easy use with the FREQ knob at the top and patch points at the bottom.

6. The µVCF is an amazing value both used and new.

7. The µVCF blends in, this filter is short on character but doesn't draw attention to itself. This can be good if you don't want your entire track to sound like patches from the same synth.

8. I'm a fan of filters that include commonly used utility functions such as dual inputs with a mixer. While the Intellijel μVCF doesn't have dual inputs, it does include attenuverters on the FM inputs which conserve attenuverters for other duties.

What Does The µVCF Sound Like?

I haven't seen any videos specific to the Mother 32 and the µVCF, minus one that has some West Coast style robot chatter, but here are a few nice videos that demonstrate the µVCF's utility.

What are your thoughts on the Intellijel VCF? What VCF did you add to your Mum?

Friday, December 30, 2016

Expanding the Mother 32 - Part 3 - All About That Bass

Where Is The Sub-Oscillator On The Moog ?

I pre-ordered my Mother 32 as soon as Moog announced it. After receiving it, the poor synth sat for months as I was disappointed that I couldn't easily access the sounds the baby Moog was capable of producing. It seemed that Moog omitted many essential features and one of those omissions was a sub-oscillator. Also, I was used to working with my Bass Station II and not a modular type synthesizer.

Rather than part with the baby modular, I decided to double down and purchased another Mother 32 along with a 2 tier stand kit. Initially this seemed like a great idea but I quickly understood that unless I was using the sequencers on both synths that my money would be better spent on building on a single Mother 32's strengths. So I sold one of the Mother 32 voices, kept the case, and went about choosing modules to expand the Mother 32.

I needed a 2nd oscillator and I noticed several VCOs didn't have sub-oscillator outputs. I learned that synth knob wigglers take the original VCO output and divide the frequency by 2 to produce an output one octave down from the original. This simple function is commonly performed by flip flop circuits. The resulting sub-frequency is then mixed with the original VCO signal by using a mixer. There are modules such as the Blue Lantern Subharmonics Generator that are dedicated for the purpose of providing sub-oscillator outputs but another option is to use a clock divider such as the low cost Doepfer A-160-1.

The Doepfer A-160-1 and the Mother 32

I chose the Doepfer A-160-1 module for my Mother 32 outfit for a variety of reasons.

1. The module is useful for more than sub-oscillator tones.
2. It's intuitive unlike more complicated modules such as Function or Maths.
3. It's cheap, around 80.00 USD new
4. It's small, 4hp, and it has six blinking LEDs. :)

If you've prepared your Mother 32 for expansion then adding an A-160-2 isn't a big deal. I've expanded my Mother 32 with a 2 tier rack kit, Moog 60hp skiff, and TipTop μZeus micro power supply with flying bus boards.

Patching the Mother 32 and the Doepfer A-160-2 

Here is a quick and dirty pic of the A-160-2 installed in the top tier of my Mother 32 outfit. As you can see, the Doepfer module is sharing real estate with a few other friends. Don't be surprised if some of these modules go, I'll rotate modules in and out of here until I settle on a single configuration for a bit.

Using the A-160-2 is super easy, start by feeding the Trig In with either of the Mother 32's VCO outputs. Next, connect one of the outputs of the A-160-2 to your EXT AUDIO jack on the Mother 32. The /2 output is one octave down, the /4 is two octaves down, and so on. Then use the Mother 32's MIX knob to blend the original VCO with your new sub-oscillator. If you desire more bass madness, connect a second output from the A-160-2 to MIX 1, and the original output you choose to MIX 2. Then take a patch cable and patch VC MIX to EXT AUDIO. Now you can blend the amount of sub-oscillator as before in addition to balancing the mix of the two sub-oscillators using the VC MIX knob. You could even modulate the VC MIX with the LFO by patching one of the LFO outputs to the VC MIX CTRL.

Final Thoughts

For the money, you unlock a LOT of potential from the Mother 32 by adding the A-160-2. Blending in lower octaves gives the Mother 32 a dark menacing presence it can't pull off in its factory configuration.  The VCO I choose and the A-160-2 consume a total of 10hp, you can easily find VCOs with a sub-oscillator output at that size, but not many VCOs output a sub-oscillator more than one octave down nor would they allow you to leverage the included clock dividing circuit for other uses. Do you have any creative patches using the A-160-2? If so, please share in the comments below!

Friday, December 23, 2016

Expanding The Mother 32 - Part 2 - In The Interim

So I've decided to take a few modules that I've planned to use in my DIY rack and put them in the Mother 32 skiff for now. I starting to think the Mother 32 will make a funky little groove box. Now if my AC adapter for the uZeus will just show up!

1. Roland System-500 512 - I'm hoping for some old school VCO action with this guy. I love the sliders.
2. Make Noise ModDemix - Useful for ring-mod and other bipolar VCA type functions.
3. Vermona VCDrive - I've never heard it. I bought it on a whim on Black Friday 2016. It was really $$$ for an overdrive so lets hope it delivers.
4. Intellijel uVCF - This should give me some good self oscillating sine waves to use for FM. Hopefully the high pass sounds nice so I can run it into the Moog low pass filter for some fat bass sounds. If so, I doubt it will leave this rack.
5. Erica Synths Quad VCA - A VCA that will definitely move to the DIY rack after I assemble my Synthrotek Dual VCA DIY kit.
6. TipTop uZeus - I've mounted it on the front for now. I'm going to attempt to cut a slot in the back of the case and mount it there in the future so I can free up 4hp in the 60hp skiff.

Expanding the Mother 32 - Part 1 - Always Measure First

Since discovering ModularGrid.Net I've spent far too much time attempting to stuff a 60hp wide Mother 32 skiff with the most essential companion modules to get the most out of the Moog Voice. As a result, there has been a parade of Eurorack modules showing up at my doorstep via UPS. Sadly, I assumed that my first choice in VCO, the slim and affordable Doepfer A-111-3, would fit into the Moog 60hp skiff, it does not fit. :(

The Doepfer A-111-3 is too deep due to the arrangement of the reproduction CEM 3340 chip on the circuit board. It's interesting how simple of a PCB the A-111-3 uses. Perhaps we'll see a DIY VCO based on the CEM3340 with buffered outputs in the near future.

The Doepfer A-111-3, circuit board view.

If you've never seen how thin a Mother 32 is, here is your chance. I've also included a photo of the little audio output / power supply Moog uses. The Moog power supply is NOT Eurorack standard however the Mother 32 has a Eurorack standard power connector on the PCB.

So , if you read this post, do you have any suggestions on a space saving triangle core VCO that I can put into this case? If so, please comment below.

Saturday, December 17, 2016

Witness The Dreadbox NYX

You know, I really liked the Erebus but something about it just didn't quite do it for me. I nearly pulled the trigger a few times but I just couldn't get over the Erebus's lack of oscillator FM. I emailed Dreadbox about it and they promptly told me how to mod the synth but it wasn't a project I wanted to get into.

Ok Dreadbox, now you have this synth nerd's attention.

I love the idea of modular stuff but a self contained synth module is a thing of beauty. Have you ever heard an Intellijel Atlantis? Or better yet, how about a jam with both an Atlantis plus a Dreadbox. :)

A well conceived analog synth voice is easy to navigate and should lend itself to melodic creativity. The new NYX certainly sounds the part and I dig the easy modulation routing , intuitive layout, and sliders. I see Dreadbox isn't touting through hole construction on the NYX as they did on the Erebus. Regardless, kudos to Dreadbox on such a great box. It's a great time to be into analog don't you think?

Saturday, December 10, 2016

In the Beginning There Were VCOs, and They Were Good

Sooooo, where do I begin? I've always been a bit of a nerd, I love to geek out, I memorized Radio Shack catalogs in the 80s for fun, and my childhood electronics kit was a most cherished posession. I started jamming on guitar about six years ago but to be honest, I'm awful at the axe. I started keyboard lessons at the end of summer, and while I'm not a natural, it's coming to me easier than guitar ever did.

The reason I started taking lessons was due to the purchase of a Novation Bass Station II on Black Friday of 2015. I had decided that I wanted to tinker with analog synths and Pro Audio Star had a stonking good deal on the Bass Station II. For grins I checked their site on Black Friday 2016 and they had them for 300 bucks, which is mind boggling when you compare the Bass Station II to other 300 dollar synths. The Bass Station II, or BSII as it's often referred to, seems to have started out on the wrong foot with the online community. I suspect the main reason is the lack of adjustable filter tracking. After that a lot of peeps started to claim the Bass Station II sounded vanilla, lacked character, etc. Contrary to the internet's lack of enthusiasm for Novation's synth, I find the Bass Station II sound to be warm, rich in analog character, and flexible. Attack Magazine named it one of the 10 best monophonic synths and Paul Hartnoll of Orbital seems to like it too.

There are a few things I don't like about the BSII.  I'm not a fan of step sequencers where you can't visualize the pattern and mute notes but the BSII's step sequencer gets the job done in a pinch. I also find the distortion a bit aggressive, there isn't a warm sweet spot, but you can always add saturation to the signal externally. I doubt you'll need to do it often as this board sounds warm and analog to my ears. Finally, some of the function key combinations are a bit odd, and I find myself forgetting about some features, the slew feature comes to mind.

The BSII is monophonic, which means you play one note at a time. This may sound limiting but when combined with some external sequencing it can be extremely powerful. Check out some examples of sequencing with Elektron gear.

A lot has happened since I bought the BSII but that's another blog for another day. I have several analog synths now but I just love this thing to bits.

Thanks for Reading