Thursday, May 24, 2012

A-127 Triple VC Resonance Filter Videos by Raul Pena

Raul Pena (from ) has published the four A-127 Triple Voltage Controlled Resonant Filter tutorial demo's.
As most of you already know, this is one of my most favorite Doepfer filters, see more of my posts about this module HERE, so i was kinda looking forward to these video's.

Video 1: Doepfer A127 VCRF Triple Voltage Controlled Resonant Filter Part One-Introduction

" Description and Demonstration of the Doepfer A127 VCRF Triple Voltage Controlled Resonant Filter.Focus on Basic Features. One of four videos. Next in series Modulation.
Audio Loops by Raul Pena.Sound and Video by Raul Pena."

Video 2: Doepfer A127 VCRF Triple Voltage Controlled Resonant Filter Part Two-Modulation

" Description and Demonstration of the Doepfer A127 VCRF Triple Voltage Controlled Resonant Filter. Focus on Modulation of Resonant Filters. Number Two of four videos. Next in series More Modulation.
Audio Loops by Raul Pena. Sound and Video by Raul Pena."

Video 3: Doepfer A127 Triple Voltage Controlled Resonant Filter Part Three-More Modulation

" Description and Demonstration of the Doepfer A127 VCRF Triple Voltage Controlled Resonant Filter.Focus on Modulation of Resonant Filters by Sample and Hold.
Number Three of four videos. Next in series Audio Rate Modulation.
Audio Loops by Raul Pena. Sound and Video by Raul Pena."

Video 4: Doepfer A127 Triple Voltage Controlled Resonant Filter Part Four-Audio Rate Modulation

" Description and Demonstration of the Doepfer A127 VCRF Triple Voltage Controlled Resonant Filter.Focus on Audio Rate Modulation of Resonant Filters.Demonstration of audio distortion with the A127.Number four of four videos.Audio Loops by Raul Pena.Sound and Video by Raul Pena. "

Wednesday, May 23, 2012

A-116 Voltage Controlled Waveform Processor

Another good way to mess up your audio (and CV signals) is with the A-116 VC Waveform Processor module.

After the input amplifier, the signal goes through two parallel processors: a clipping circuit, and an asymmetrical amplifier.
In a way you could see this module as a cut-down version of the A-137-1 that i reviewed in an earlier post.
Cut-down, but still very effective...

The processed signals are added together and sent to the output.
Clipping-Level and Symmetry amounts are manually controllable, but can also be modulated by control voltages like ADSR's, LFO's, Noise, etcetera.

It is a fun module to experiment with, although i haven't used it in a while.
Take a look at the video by Hawklord2112 that gives a nice impression of what this module can do.

Video: A-116 Demo

" basic functions of the A116 VC Waveform Processor from Doepfer. "

Find more of his videos at

Friday, May 18, 2012

A-137 Wave Multiplier

I might have underrated the A-137-1 Voltage Controlled Wave Multiplier a bit. Until lately...

The basic idea of a wave multiplier is to multiply the waveform of an incoming signal and add harmonics to a signal that contains none or only a few harmonics (e.g. sine or triangle waveform)
The A-137 can be used with signals rich in harmonics too (e.g. saw) but the effect is not as remarkable as for triangle or sine waves.
For rectangle signals none or only little effects are obtained.

The A-137 is a very interesting module, in a way it is quite similar to the A-136 Distortion/Waveshaper
You can compare it with four simple A136 modules in series. (The A136 is basically like a guitar distortion stompbox with different distortion levels for the positive and the negative parts of the signal.)
Only in this module you do not have separate access to the two half waves and to the parameters of the individual stages.

The parameters of the A-137 are:
- Multiples: defines the number of basic wave multiplications within one period.
- Folding Level and Symmetry: the upper and lower clipping levels of the wave folder units are controlled.
- Harmonics: adds some harmonic content by sharpening the waveform edges and adding overshoot peaks. It works a little bit like the resonance control of a VCF.

All 4 parameters can be manually adjusted and controlled by external voltages.
It is a lot of fun to experiment with this module, with all different parameters controlled by different CV sources like LFO, ADSR's, Ribbon Control pressure and sequenced triggers for example.

The only thing i dislike about this module is the unpredictability factor.
You should be carefull for a 'damping' effect that can occur when different parameters interact with eachother.
But on the other hand; the module is fully DC coupled, so even CV signals can be messed up with this module.

Check out the audio examples on the Doepfer site that explain the function of the module and its parameters.

Sunday, May 13, 2012

Future Modules Update

Last week, Dieter Doepfer took the time to answer some questions in the Yahoo Doepfer A-100 Usergroup on the state of the new modules that will be released this year. I did mention most of them earlier, so no big news this time, but some really informative background info.

About the A-190-5 (four voice polyphonic Midi to CV/Gate interface):
" The new A-190-5 prototype (version with LC display) is on my table since a couple of months. But we did not continue because of some more important projects (e.g. Dark Time, Dark Energy II). I think we will be able to finish the hardware until summer (end of summer is in September :-) but I don't think that the final firmware with all planned modes will ready at that time. But we plan to add the firmware update feature via the USB interface."

Doepfer A-157 Trigger Sequencer, as shown at
MusikMesse 2012. Picture by @Cymatics
A-157 Trigger Sequencer -update:
" We are working on the A-157 right now. The new button/LED board with 16x8 is already made and tested. But we are about to redesign the control board as we determined that the microcontroller used in the first prototype (the pictures with the 8x8 board) is not powerful enough for all planned features. In addition the manufacturer announced the discontinuation of the chip. So it will still take some time until the module is ready."

He continued:
" I hope that these 3 new modules will available during this year: A-192-2 /CV/Gate-to-Midi/USB converter), A-190-5 (polyphonic USB/Midi-to-CV/Gate interface), A-157-1 (16x8 LED/button board with 8 trigger outputs), A-157-2 (control board #1 for A-157-1).
But I'm not sure about the order of the release dates.
Probably the A-192-2 will be the first one as the development is nearly finished (we have to built one more prototype and hope it will be the last one).

We (also) think about a "real" ASR (analog shift register) module because the A-152 cannot be used as ASR in all applications.
But this has no priority at the moment and is not yet mentioned in our list of planned modules."

Note: Please don't call or mail them too often at Doepfer about release-dates or updates of future modules. The Doepfer website is updated very regularly, so you will find all the latest info THERE...

Tuesday, May 08, 2012

A-140 ADSR Envelope Generator videos by Raul Pena

It's amazing how fast Raul Pena keeps on publishing those A-100 tutorials.
Here are the first three parts (of 4) of his latest videos...

Video 1: Doepfer A140 ADSR Envelope Generator Part One-Introduction

" Description and demonstration of the Doepfer A140 ADSR module. Demonstration of creating a kick drum with a filter and shaping with the A140 ADSR. Sound and Video by Raul Pena."

Video 2: Doepfer A140 ADSR Envelope Generator Part Two

" Part Two in the Doepfer A140 ADSR Generator demonstration.Experimentating with shaping with the A140 ADSR in the Medium setting.Also includes demonstrations of retrigger and inverse envelope.Sound and Video by Raul Pena."

Video 3: Doepfer A140 ADSR Envelope Generator Part Three-VCO Patch

" Description and demonstration of the Doepfer A140 Envelope Generator in a VCO Patch. A brief description of the A190-Midi to CV Module is described and sound demonstration. Sound and Video by Raul Pena."

Video 4: Doepfer A140 ADSR Envelope Generator Part Four- White Noise Patch

" Description and demonstration of the Doepfer A140 Envelope Generator in a White Noise Patch. A brief description of the A190-Midi to CV Module is described and sound demonstration. Sound and Video by Raul Pena "
Don't forget to check out Raul's site at

Sunday, May 06, 2012

200th PatchPierre Post

Woooot!... but you might have guessed that already...

Another small 'milestone' for the blog, my 200th post, in a little over two years of blogging here.
I will try to keep the tradition of writing a dedicated post every 50th up... if you like it or not ;-)
Thank you all again for the interest in my site (6000 pageviews last month) and for all your promotional work, re-tweets and positive responses, that really means a lot to me every time.

My A-100 rack and MAQ16/3 sequencer
Some of you might know that a column on the left side (bottom) of the blog always shows the posts that were visited the most, but strangely enough, my 50th, 100th and 150th post are all in the top 5. (probably this one will soon be there too?)
I find this a bit weird, because i personally expected my most interesting posts to rank higher, and i even hoped that the one i enjoyed writing the most would end up highest... but no...
It is still very hard to predict what post will be read the most, but that keeps it a nice challenge for me...

I do have some personal favorite posts, sometimes because of the fun i had researching it, or because they were so interesting for the readers and/or news-worthy that other blogs re-posted them (often with a proper link to my site).
If you are new here take some time to (re)-read my blog-posts this weekend, you will probably find something interesting.

Here are a few of my own favorites in random order; is one of them, i love to write about functions of modules that you (still) cannot read anywhere on the Doepfer website...

My first post that i wrote after some intensive personal emailing with Dieter Doepfer (who actually does a great job doing customer support) is also in my favorites list;

My post about the announcement and specifications of the Dark Energy II was re-posted on almost any respected synthesizer-blog and should not be forgotten here;

My favorite posts from the DIY/Modifications -section;, my coolest modification so far.

and finally this one;
I must have had a vision at the time i wrote this, because Doepfer recently announced a module like this (read all about that HERE)

As you can see i left the Raul Pena video's out, because all props for that go to him of course...

My personal taste might be a bit different than yours...
Feel free to leave a reply on what your favorite post was, or to submit topics that you like to read more about.
All feedback is welcome and I will take all your suggestions in consideration.

Thursday, May 03, 2012

Doepfer M.A.U.S.I.

The Doepfer MAUSI (MIDI-Analog / SYNC Interface) was released in 1995 (around the same time as the A-100 system) and was a MIDI-to-CV and MIDI-to-SYNC interface to control analog vintage synthesizers, bass lines and/or drum machines via MIDI.

Doepfer MAUSI front

It was a small, half 19-inch sized grey box, and until a few weeks ago, i never realized why the Doepfer MAUSI looked so familiar to me.
An email from Dieter Doepfer confirmed that not only on the outside, but also internally this module is for 95% the same as the A-190 MIDI-to-CV/Gate/Sync Interface.
One of the small differences between these two modules is that the MAUSI had a DIN SYNC output, and the A-190 has a clock and a reset output.
Doepfer explained to me: " In modular systems the RESET feature was more popular than the Start/Stop of
the DIN SYNC, but after all it's nearly the same (just the opposite levels: Start/Stop of DIN SYNC goes high at the Start and low at the Stop, RESET goes low at the Start and high at the Stop)"

Doepfer MAUSI backside
MAUSI allowed you to control synthesizers via either V/octave (Moog, Roland, Sequential, A-100) or Hz/V characteristics (Korg, Yamaha).
Beside that, you could also switch between gate/trigger (+5...+12V) or switched trigger control (S-Trigger).

Around 400 MAUSI's were made from September 1995 until April 2000
MAUSI included an external power supply for 230V AC.
For other mains voltages the power supply had to be purchased separately by the customer. (7...12V DC/500mA with 2.1 or 2.5mm connector required).

Find more info in the English User's Guide of MAUSI.