CD-Tip III : Analogklang - Modulsystem A-100 Demo CD

This CD was published by Doepfer in 1995 to show off their then brand new A-100 modular system. It has 29 tracks and a large, colorful, fold-out booklet (in German) with a description of most of their early modules.

All the basic modules are demonstrated on this CD, that was produced by Andreas Merz from Weltklang and  narrated in German by a vocoded voice. The tracks are short, between 25 seconds and 3½ minute, what brings the total length of the CD to just 30 minutes.
This CD itself must be a collector's item by now i guess, because the item isn't available anymore on Doepfer's website. I'm quite sure i won't sell my copy... ever. This CD still means something special to me, and i did listen a lot to it, even before i bought my first modules.

Although the CD isn't available anymore, all tracks ( and some other sound-examples ) are still available for download HERE ( ...sadly enough in a poor ( 16Kbps) quality due to file-size decisions, but if you really need better audio-files you can contact Doepfer for better ones )
A must-have /or at least must-listen CD for all the real A-100 geeks and you might even get some new, fresh ideas out of it.

Modifications III : A-127 Triple Resonance Filter Expander (part 2)

Hmmm... that went faster as i expected.
My brand new self-made A-127 Expander Module is now almost finished.
( Find part 1 HERE)
The switches are wired too, and the overall look of the module is even better as expected.

I did have some trouble with drilling holes through the aluminium front-plate at first, but it seems i aligned the sockets nice enough with the output sockets of the A-127 itself.
The switches work smoothly and the 'new' 12 dB filters sound sweeeeeet.

I'm very happy with this module, and glad that i went with this option instead of just putting switches on the A-127's front panel.


The wiring of the modules on the backside was quite simple. Red wires were used for switching between the different filter-modes, the blue ones the the audio-multipliers, and yellow ones (not visible in the picture) for the lower switch.
I did the soldering without removing anything from the module, but you might want to remove some components for easier access.

Instead of soldering you can also use small (0.1") wire-sockets at the board's jumper-spots. An example with detailed information of this can be found HERE

Update March 10, 2014
Doepfer announced an official Breakout Module for the A-127,
find out all about it at http://patchpierre.blogspot.nl/2014/03/doepfer-127-bom-filter-breakout-module.html

Modifications II : A-127 Triple Resonance Filter Expander

Now that i finished my first 'real' module-modification i couldn't wait to start with the next project.
At first i wanted to replace a red LED for a blue one on one of my modules myself, but i couldn't decide which module i should pick for this... and i'm still not sure, but that can wait....

Another plan that was in my head from the beginning was the placing of 3 switches on the front-plate of my A-127 Triple Resonance Filter. There are 3 jumpers inside this module that allow the user to switch the filter-type of each of the three channels between Band-Pass (standard) and 12 dB Low-Pass. I have seen some examples on the web of this modification, most of them just with the switches mounted on the A-127 itself, but unexperienced as i am, i was too afraid to damage the front-panel and went for an Expander Module design.

So that is why i am building it into an official 4HP blind-panel that i bought from Doepfer. Each of the three A-127 channels on my expander module design will have a switch to switch the channel's filter-mode and will also provide an extra (linked) audio output.
( mainly to fill up the space, but i aligned these with the A-127's original outputs to make it look more like an official Doepfer module ) .

To complete the expander module i also want to place a switch at the bottom that has the function of the J3 jumper that is inside the A-127 module on the mix circuit-board. This switch can put the module in a mode so that both levels of the filter and the original can be controlled with attenuator 1 ( audio level in )

I am not finished with the project yet, the mounting of the switches and extra outputs is done. Wiring is the next step, i'll write another post on that later this week...
Find Part 2 at http://patchpierre.blogspot.nl/2010/12/modifications-iii-127-triple-resonance.html


Update March 10, 2014
Doepfer announced an official Breakout Module for the A-127,
find out all about it at http://patchpierre.blogspot.nl/2014/03/doepfer-127-bom-filter-breakout-module.html

Modifications I : A-156 Quantizer Follow

A-156 with modification

Yesterday i picked up the spare parts that i ordered from Doepfer; a few switches, 3.5 mm sockets, LEDs and blindplates of different types and sizes. Now that i have them i couldn't wait to start with my first project.

One of my personal little annoyances that i have with the A-100 system are the tiny internal jumpers inside of some modules. Behind these jumpers are sometimes great functions that make these modules a lot more flexible.

Where i can, i will try to replace the internal jumpers with switches on the front on more modules, but i started with the A-156 Dual Quantizer Module.

A-156 after removing all the knobs
and frontplate

This module has two separate Quantizers, one that only uses a semitone-scale and Quantizer 2 that has much more options like minor/major/chord/quint/6th and 7th scales. There is a way to let Quantizer 1 follow Quantizer number 2 by replacing an internal jumper, but why there? It is probably a cost-saving thing from Doepfer's side but there is enough room on the frontplate of the module to place a switch with the same function. You can find a neat step-by-step guide with pictures on how to do this HERE , but it is quite easy.

Wiring the new switch

After removing the frontplate and drilling a hole for the new switch ( there is enough room above or under the printed 'Options Quantizer 2' text ) i could fit a new Doepfer 1-0-1 (on-off-on) switch in the hole and mount it back together again.

A-156 detail close-up

The wiring was quite simple, so even with my mediocre soldering-skills this was a piece of cake for me. The result is a simple and invisible modification that works perfect. Switch down couples the 2 quantizers, switch up puts quantizer 1 in it's original mode.

Okay... a similar result can be obtained with the use of an extra multiplier, but i found this one more adventurous... and rackspace-saving.

Now its time to experiment with the new options that i have. I can think of some nice patches already, but there are also some good suggestions for the use of this module and this modification at Synovatron's blog.

PatchPierre Mobile Template (beta)

Good news for PatchPierre.net visitors on Android, iPhone and other mobile devices. As of now the site is visible in the mobile template, with quicker loading times and easier browsing through the posts.
The site now automatically  changes into the new template when you visit it, but you can also get there by scanning the QR code or following this URL:
http://patchpierre.blogspot.com/?m=1

Nokia / Symbian users can still download the
PatchPierre Mobile App HERE ( 3500+ downloads already )

UPDATE December 25th 2010:
Thanks to the OVI-store, people on Android,iPhone or other mobile devices can also use the OVI-Template of the PatchPierre site... it even looks better than Blogspot's own template.
Try it out and point your browser to http://tinyurl.com/PatchPierreMobile 
( Don't forget to bookmark it! ) 

SiteTip II : Doepfer A-100 series modifications by Nick Keller.

Another nice site i stumbled upon in the last weeks in my search of Doepfer DIY info is the Doepfer A-100 series modifications site by Nick Keller at http://www.analoguehaven.com/usercomm/diy/

This site offers some great (and easy-looking) Doepfer-modifications, complete with step by step explanations and pictures. Most of the modifications are simple but very usefull and consist of adding more switches, inputs and outputs to the frontpanel. Very interesting stuff... I'm looking forward to try some of the examples and hope that the parts i ordered from Doepfer will arrive soon, so i can start experimenting on my first Doepfer-projects.

The mods described will most likely void any warranty and, if not done carefully, can damage the circuit board, IC chips, and faceplates.

Quotes III : Robert Moog

" I'm an engineer. 
I see myself as a toolmaker and the musicians are my customers... They use my tools."

Robert (Bob) Moog

DIY Projects I : The Beginning

I bought my first prototyping board (or breadboard) and some jumper-wires last week, it's time for me to start learning about electronics and electonic circuits.

The board i got was of the Velleman brand, and to be sure i had enough room on it i bought one of the bigger boards, still for under 20 Euro's.
I also bought a small Velleman Voice Changer Kit (MK171 - 9,95 Euro) , the only audio-related DIY-project i could find to experiment with. Like i said earlier this stuff is quite new to me, and my first attempt will be the mounting of all the parts of the kit onto the breadboard. This seems like a good practice for me to learn more about the components and their functions.

I did learn a lot on YouTube last weeks about the basics of breadboarding and electonic components, and there are a few good (and free) tutorials on the MIT OpenCourseware site ( both video's from lecture 12 are highly interesting and deal with basic sound creation with electonics ) The 559 pages thick lecture notes PDF  that completes this course is also free available at the site, and features the whole course on paper.

The kit is a voice changing kit that can basicly changes your voice into a high, low or robotvoice. I haven't heard yet how it will sound, but the idea and basic modification possibilities are looking great.

I see this as a sort of a side-project, that will hopefully merge into my A-100 system at one point and i'm looking forward on how it will sound. I'll keep you updated.

A-114 Dual Ring Modulator

A Ring Modulator is a signal-processor that produces a signal out of two different audio inputs.
This output signal is the sum and the difference from both inputs, and leaves the original frequencies out.

It is an ideal module for producing metallic or bell-like sounds, but you can also (re-)create other weird sound-effects with it, like for example the distinctive "Daleks"-voices from the classic Dr. Who series, created in 1963 by the BBC Radiophonic Workshop.

Besides voices, you can also input all kinds of other (amplified) instruments through the ring-modulator.

The Doepfer A-114 Dual Ring Modulator is in fact two ring-modulators in one, which makes it even more flexible. Theoretically you can use the output of the first ring-modulator as input for the second one. The A-114's manual has some nice other examples on how to start patching, but with a bit of imagination you will quickly come up with your own ideas.

You can find some more interesting ring-modulation (DIY) info HERE

PatchPierre Mobile App for Symbian Update

Version 3 of the PatchPierre Mobile App is now available in the OVI-store. 
The ultimate way to watch PatchPierre's content on your Nokia device. It works on all Symbian and selected S40-devices.

The app enables easy browsing through the PatchPierre posts and comments and also links to the original articles.
Added in Version 3 are the PatchPierre Twitterfeed and my YouTube Videosection with jams, demos and other music made my me. Find it on the web at http://www.youtube.com/netpierretv

The app will stay free in 2010, the 1 Euro that it will cost in 2011 will be spent on upgrading my A-100 system and maintaining the blog. 

All other donations are welcome too, there is a PayPal donation button in the blogs' right column.

Click HERE for a direct link to the OVI Store


More screenshots after the break: