Saturday, January 19, 2013

A-142-4 plus Expander Demo by Hawklord2112

Regular video-uploader and contributor to the blog Hawklord2112 uploaded another nice new video.

He bought himself a new A-142-4 Quad Decay module and also an extra expander module for it.
Each of the 4 sub-units of the A-142-4 has a pin header with two pins available.
When the two pins are shortened (e.g. by means of a jumper on the PCB board or a toggle switch connected to the two pins) the corresponding sub-unit changes to a loop mode. 
In this mode the unit triggers itself like an LFO..

The expander is made of a pre-manufactured panel, punched for 8 sockets, almost identical to the A-180 front panel but without the printing.
Those panels are very useful for DIY-projects like this.
In his video he explains how it all works.

Video: A-142-4

"Basic demo of the Doepfer A142.4 Quad Decay generator and DIY breakout expander"
Uploaded by hawklord2112

Thursday, January 17, 2013

A-128 Modification by Ernst van der Loo

Dutch Sound Designer, Engineer, Composer & Performer Ernst van der Loo posted a few pictures of his latest DIY-project in the Doepfer A-100 Facebook group.

Tools of the trade and lots of wire
The project involved creating 15 individual outputs for his Doepfer A-128 fixed filter bank.

Module A-128 (Fixed Filter Bank) is a filter bank, made up of 15 parallel band pass filters, all with fixed middle frequencies and bandwidth.
Each band pass filter has its own amplitude control knob, with which that frequency band can be attenuated. 
The bandwidth of each of the filters is approximately half an octave.
The signal at the original output of the A-128 contains a mix of all the filters, depending on the position of each one's amplitude control knob.

Finished project 
Ernst used an 8HP blind panel to create the expansion board for his A-128, drilled 15 holes, mounted the mini-jack-connectors and connected them with the correct terminals/outputs on the A-128 PCB board.
There is even the choice between pre-attenuator terminals (fixed volume) or post-attenuator.
You can find the document that shows how to add these single outputs to the filter bank A-128 in THIS PDF (from Doepfer's DIY page)

Ernst commented on the end-result:
 "Not too happy with the alignment of the mini-jacks yet. Maybe I'll need a new drill exercise..."

Maybe he should have saved himself the trouble, because if desired Doepfer can carry out this modification in the factory  (price for blind plate 8HP + 15 sockets + about one hour working time) for about Euro 100 altogether.
Pictures used with kind permission by
 http://www.ernstvanderloo.com

Monday, January 14, 2013

Doepfer Sound Sampler (1984)

Doepfer 8-bit Sound Sampler
On a random search on the internet for rare Doepfer products i came across this module in an old Matrixsynth post:
This Doepfer Sound Sampler module (8 bit voltage controlled sampler with interface and sampling software for Commodore 64) was made by Doepfer in 1984.

Sound Sampler book 
by Dieter Doepfer and 
Cristian Assall
The Doepfer CV/Gate controlled modular Sound Sampler system was available as a kit between 1984 and 1990.
The complete system was also described in detail in the book written by Dieter Doepfer and Cristian Assall called "Sound Sampler" (published by Elektor ISBN 3-921608-44-9) in 1988.
This book was dedicated to building an 8-bit modular sampler that could be edited with a Commodore 64 home-computer.
All schematics are in the book, with all PCB designs and front-panels for all modules: input, memory/sampling card (with CV/Gate), loopcard, C-64 interface and compressor/expander.

Picture via Gearslutz
Every sampler module had its own memory.
There was software available that could handle sampling, FM synthesis, Wavetable synthesis, Fourier synthesis and Waveshaping synthesis.
The C64 could be used only to modify the sampling memory (sampled sound or sound generated by software synthesis like FM or Fourier), up to 8 sampling voices.

Most of the PCB board was covered by the memory chips that were pretty expensive at the time.
The picture below shows a 6-Voice system, the Input/Interface module is left, then 6 times the Memory-Card, each with a HS-VCO to get the pitch and a Curtis filter.
Apart from the sampler was a CV/Gate controlled stand-alone unit (not on the pictures)

Later Doepfer added another extension card, the so-called CCU (computer control unit). 
With this unit it was possible to define loops with free adjustable start and end position (the software helped to find zero-transitions for a glitch-free loop), and the unit could now be fully controlled by the computer (also pitch via high-speed DCOs). 
Also an expander/compressor was available but the improvement of this addition was very small from Dieter's own point of view.

6 x Memorycard, 6 x VCO,
6x Curtis filter
Around 300 kits were sold, partly because around the same time (1984-1988) Ensoniq released their Mirage sampler that was cheaper (and easier to use) than the Doepfer sampler.

Dieter: "To some extend this was also the beginning of the Eurorack standard (instead of Doepfers/DD Systems earlier Formant sized modules) as the front panels already had the same dimensions and mounting positions as the A-100 that started in 1995."

This module was the precursor of the A-112 that was released more than a decade later, but in the A-112 one small chip contains twice the memory of the 16 large chips of the old sampler.

Special thanks to Dieter Doepfer for all additional info

Wednesday, January 09, 2013

LaserLoper by Gijs Gieskens

Laserloper eurorack module by Gijs Gieskens
As you all know, besides my interest in Doepfer modules i also love all other original eurorack concepts.
This one popped up on the web today, a creation of Gijs Gieskens (http://gieskes.nl) from the Netherlands.
(...also my home-country)

His latest module is a random noise generator, only a bit different than other ones.
This one is based on a small hourglass and laser technology.
As Gijs describes it on his website:
" The laser-beam seems to get bent by the falling sand (if it is sand) and shine onto the LDR (Light Dependent Resistor or Photoresistor), generating a random noise signal."

Video: Laserloper

More info at http://gieskes.nl/undefined/eurorack/?f=laserloper
(He also sells stuff... and there are many other cool eurorack creations on his website
- check out the VCOFan for example)
Find Gijs on Twitter at https://twitter.com/g1j5

Monday, January 07, 2013

BookTip XIII: Analog Days: The Invention and Impact of the Moog Synthesizer


I have had 2 whole weeks off from work this holiday season, so i had enough time to read a few interesting synth-related books.

The first one i read was 'Analog Days: The Invention and Impact of the Moog Synthesizer' by Trevor Pinch and Frank Trocco.
It's a very interesting book (368 pages) that was published in 2004, and that tells the story about Robert (Bob) Moog, synthesizers from the mid-60s to the mid-70s in general and about the Moog company and its products.

The book has a foreword by Bob Moog himself (he passed away a year after the publication of this book) and the writers have spend a large amount of time and effort into making it.
The book is filled with stories by musicians, technicians and other pioneers from that era where everyone seemed to share a same passion for analog synthesis.

The list of interviewed people for this book is too large to mention, but it includes people like Don Buchla, Suzanne Ciani, Keith Emerson, Rachel Elkind, Tom Oberheim, Alan Pearlman (from ARP) and many more.
That's a very impressive list, and the whole book is written in a chronological style, filled with many anecdotes and interesting facts, what makes it fun and easy to read.
A must-read in my humble opinion, if you are interested in this kind of stuff, of course...

Info: http://books.google.nl/books/about/Analog_Days.html?id=3hjvWzkMK-sC …
Harvard University Press, 15 nov. 2004 - 368 pages
ISBN-13: 978-0674016170

Find my earlier BookTips HERE
My next BookTip will be published somewhere next month.

Friday, January 04, 2013

Random Video: Jamming on Doepfer A-100 Modular

Found on YouTube:
A short jam showing the possibilities of a Doepfer A-178 Theremin Controller and an A-198 Ribbon Controller combination.

Video: Jamming on Doepfer A100 Modular
" Edwin (Duo Blank) jamming on Doepfer A-100 modular synth triggering sounds notes through theremin and ribbon controllers."

Uploaded by duoblank

Tuesday, January 01, 2013

Theremin: Magic Ceramic Custom Synth

Happy New-Year everybody!
I hope you all had a great holiday season...
I found this one on the web, but it's not really new...

Video: Magic Ceramic Theremin Lamp Doepfer A-178
" The first test of the Magic Ceramic Theremin lamp. 
It was developed as a peculiar piece for the opening of the Exhibition of several ceramists in Gallery Artibrak. from November until 28th of December 2011.
A Theremin is normally step-less, but in this case an A-156 is used as a quantizer..

Small explanation for those who are not familiar:
In this magic piece of ceramic two antenna's are integrated. 
One antenna for the volume and one for the pitch. 
The instrument does not have to be touched. 
The volume can be controlled by your left hand (when approaching it the volume increases), the pitch can be controlled by your right hand (when approaching it, the pitch of the sound goes up). 
 By approaching the antenna's you are influencing the potential difference. 
Just like the antenna of your transistor radio which functions well or not when approaching it.

(Ceramic Art by Mance)
The Magic Ceramic is based on the original Theremin invented by Léon Theremin in 1919. 
That electronic instrument is step-less variable and very expressive. 
It sounds like an opera voice or violin.

This ceramic version of the instrument has a much more variety than it's original. 
You can make the sound stepless or let it be quantized, so that you hear a real tonescale/musical scale. 
The sinus-tone of the Magic Ceramic is quantized (chopped in pieces), and in the way it is presented now only the Minor notes are heard. (like the black keys on a piano) 
In this way the steps between the notes are bigger and easier to distinguish. 
Other possibilities are just Major notes or the complete tonescale, quantized or not. 
There is also a small sampler added, so when you reach the highest note a spoken voice can be heard."
More info HERE
Video uploaded by creativegallerysynth