Never Enough VCO's

The engines or hearts of all modular synthesizers are definetely the VCO's. As main sound source for your patches it seems you never have enough of them.

I own 5 VCO's at the moment, One A-111 High End VCO plus four A-110 Standard VCO's. Ideal for stacking layers of waveforms to make extra- fat sounds, and also very useable for multiple A-100 melodylines

The A-111 is the one i use most because of its extended possibilities. 

This VCO has an extended frequency range, improved waveforms, FM and Soft Sync inputs plus an extra fine-tune-controller. Ideal for controllerfreaks like me. 

It produces sine, triangle, pulse and sawtooth waveforms, which are all derived from the triangle oscillator, what does make it hard to produce perfect sine-waves ( but a little better as the A-110's sine wave )

One of the best things is that all 4 waveforms are all simultanously available at the outputs for your mixing pleasure.

The much cheaper A-110  has less controls and is based on a sawtooth oscillator. All outcoming waveforms of this module are derived from this sawtooth by internal waveform converters. This module also generates sinewaves that are not completely perfect, but to 'normal' ears this is hardly audible

I never noticed, and i guess most of us don't care and never noticed the imperfect-ness of the sinewaves of both modules.

Even on an oscilloscope it is hardly visible that the sinewaves are nothing more than rounded sawtooth-waves.

For a perfect sine wave Doepfer recommends the A-143-9 Quadrature LFO/VCO, another interesting module, that i will highlight in a future blogpost.

Note: As the special circuit CEM3340 used in the A-111 High End VCO module is no longer available the module has to be discontinued. Sales at Doepfer while stocks last !

A-100 Module Circuit Board (Picture)

Most of the Doepfer A-100 modules' circuit boards are really pretty. It is almost a shame to build them into a case...

They almost look like a well-architected mini-city on a tiny Doepfer-board, almost like LEGO- miniature-city.

Patchpierre MiniQuiz:    What A-100 Module is this?*

* Answer is HERE - feel free to take the short Poll; "  Analogue or Analog?  "

Analog Noise vs. Digital Noise

My Doepfer A-100 system includes 2 Noise different generators, the A-118 Noise/Random Voltage Generator, and the A-117 Digital Noise Generator.

A noise generator is an oscillator that produces an internal noise signal, typically white or pink noise.

Noise Generators produce random signals, containing harmonics on all frequencies, and can be modified into the desired tone. 

The A-118 produces white and colored noise. The white noise is the well-known 'hiss'.

The spectrum for the white noise has the same amount of energy in every section. 

The colored noise output of the module is a mix of blue noise ( high frequency component ) and red noise ( low frequency component )

Noise in the audio spectrum can be used in many ways, most commonly in wind-effects, or in cymbal crashes and hi-hat -sounds.

The A-117 Digital Noise sounds very different and has less control possibillities.

This module has 2 outputs, consisting of mixes of multiple oscillators to re-create vintage Roland TR-808 and TR-606 sounds like the hi-hat, cymbals and cowbell.

One output has a mix of 2 fixed digital oscillators, that can be used as a basis for the distinctive 808 cowbell-sound, the outher output has 6 oscillators to form cymbal and hi-hat sounds.

The Random outputs of both modules can be used as a Control Voltage for all kinds of stuff. I prefer the Analog Noise for that, simply because it has more controllers.

I often use it as a modulation source to add subtle changes in a filter (check out a short example HERE), but these modules can also provide interesing effects in combination with the A-148 Sample and Hold module. More on that in a later post...

Video: A-118 Demo 

A118 Noise and Random voltage generator demo made by @Hawklord2112

Booktip II - Vintage Synthesizers by Mark Vail

Another interesting read; 
The subtitle of this book: “Groundbreaking instruments and pioneering designers of electronic music synthesizers” explains a lot about the content...

This neat 300-page book, written in 1993 by Mark Vail, one of the writers of Keyboard magazine, is a very complete overview of 30 years of synthesizer history - from 1962 until 1992.
The book is full with background-stories and funny anecdotes by designers and early users and it is loaded with nice (mostly black and white) pictures.

The buying guide, the giant glossary and the comprehensive index in the back of the book make this book an unmissable read for anyone interested in (analog) synthesizers, sequencers and drum machines.

ISBN: 0-87930-275-5
More info at http://www.markvail.com/

Noise (Picture)

"Noise is a random or quasi-random sound made up of many frequencies, perceived by the ear as hiss"




*from "Vintage Synthesizers" by Mark Vail (1993)

A-164-1 Manual Gate

I love hands-on control over my Doepfer A-100 Sytem:
I simply love my Ribbon Controller, the Joystick, Wheels and Theremin Modules, and this one is also one of my favorites.

Perfect for manual ( one-shot ) triggers is the A-164-1 Manual Gate Module.

This module has 3 seperate trigger-buttons that generate a 12V voltage at their respective Gate outputs when pushed. On release no voltage is sent.

All 3 Buttons have double outputs for even more flexability and functionality, and Gate/Button 1 can also be controlled by an external signal ( e.g. the rectangle output of an LFO ),  what makes button 1 act like a momentary on/off switch. This can add some nice ( rhythmic ) effect to your patch.

I prefer to use this module as a manual trigger for self-made one-shot sounds like cowbell sounds or other weird electronic (drum-) sounds. ( Pjoewwww)
In these patches i mainly use the buttons to trigger one or more ASDR's or envelope generators

Another interesting application for this module is extreme filtering...
Because the output of each  Gate is 12 V, feeding this voltage into a CV input of a filter ( or it's resonance control ) will lead to an abrubt ( and full! ) opening and closing of the filter at the push of a button.

As with almost all A-100 Modules, possibillities are limitless.
Leave a comment if you have more interesting and/or creative use for this module.

Doepfer MAQ16/3 and Doepfer A-100 - A Dynamic Duo

If i could only advice one external controller for the Doepfer A-100 system it would definitely be the Doepfer MAQ16/3 MIDI/Analog Sequencer.

This versatile sequencer has 3 rows of 16 knobs, and outputs a CV (for pitch) and a Gate (trigger) signal for each row. It also has a MIDI input for synchronizing, and a MIDI output to connect any sound generating MIDI device.

The ease of use of this sequencer is incredible, in just a few minutes you have different (bass-) lines wobbling through each-other...

Different running modes are available for each row, such as Forward/ Backward/ Random/ Pendulum and many more, so the possibillities are almost limitless. Other parameters that can be altered in the sequencer are First/Last step, Gate time, Tempo, and almost any other MIDI event type.

My only personal negative point that i would like to mention is the limit of 30 sequence memory spaces, way too little in my opinion, and i know it is more than what sequencers could store long time ago, but hey... can't this be upgraded to 99 memories ( please!? )

There are many alternatives for the MAQ16/3, the A-155 Analog/Trigger Sequencer is Doepfers own dedicated in-system sequencer module that can be extended with the A-154 Enhanced Sequencer Controller, but still doesn't have the full funcionality of the MAQ.

(Analog) sequencers of other brands are also quite popular, some in a eurorack module form-factor, others in the shape of desktop controllers...
What's your favorite? Feel free to leave a comment below!