We have recreated what is probably the most epic and fattest sounding portable monophonic synthesiser of all time and adapted it to the Doepfer Eurorack modular synthesiser format. First and foremost the MiniMOD had to replicate the sound of the vintage Model D as closely as possible, so we have used exactly the same internal circuitry and every module runs at the same internal signal and control voltage levels as the original.
The MiniMod is based on the circuitry of most desirable Model D of all, the very early R A Moog Mk1 model with its unique and sweet sounding VCO design, the core of which uses discrete transistors only, with no integrated circuits. We have also based the transistor ladder VCF on the early design, which uses fully matched transistors throughout. Less than 300 Mk1 Model D’s were built with this very early VCO design out of a total of around 17,000 which were produced between 1970 and 1981.
The Minimod has been more than 18 months in development, thousands of hours have been spent analysing the original Model D using both real world measurement and computer based Spice circuit simulation programs, we have carefully selected components and built many prototypes before we were happy that we had done justice to the original sound and circuit behaviour.
Overview
MiniMod Eurorack modules comprise separate VCO, VCF, VCA, Dual Contour and Glide/Noise for maximum flexibility so that they can be easily integrated into a larger Eurorack format Modular synthesiser to tap into the endless control and expansion possibilities – we have removed all of the control limitations of the “closed system” of the original Model D synthesiser so that the sounds that you can now create are limited only by your imagination and the other modules that you add to your system. All of the modules can be used independently in your existing Eurorack system – want to just try a VCF or VCA with your own modules? No problem, all of the modules are compatible with the most common Eurorack audio and control voltage standards and should integrate seamlessly into your system.
We have added lots of extra features, if it was possible to add extra versatility without compromising the sound and functionality then we have done so.
Here are just some of the extra features that we have included:
VCO: – added External Sync (2 Types), Linear and Exponential Modulation, fully adjustable PWM instead of fixed pulse widths and voltage controlled PWM.
VCF: – added Voltage Controlled Emphasis using a vactrol and have added an extra overdrive capability, switchable using an internal jumper.
VCA: – added voltage control for each individual VCA (yes, the original design had two VCA’s in series!), along with an overdrive capability, switchable using an internal jumper.
Dual Contour: – added individual manual trigger buttons for both envelopes and envelope status LED’s
Glide + Noise: – added glide up only and glide down only modes in addition to the standard glide mode. We have also increased the range of the glide from the original 44 notes to 5 octaves.
A MiniMod system would comprise 3 x VCO, 1 x VCF, 1x VCA, 1 x Dual Contour, 1 x Glide-Noise and this will take up 84hp of Eurorack space, so that it will fit into 3U of rack space with a suitable Eurorack frame and power supply (not supplied) Just add a Midi/CV converter and keyboard for a fully functional BIG and FAT monophonic synthesiser. Below is an example of how to patch a 3 VCO sawtooth sound with glide enabled on all VCO’s.
IDR 37.859.000
With Waldorf KB37 … IDR 53.176.000
