150th PatchPierre Post

Woooooot! ...all over again. :-)
My 150th post already, who would have thought that?
I didn't expect to still be able to post every 3 to 4 days, because i thought there wasn't much to blog about anymore, but it looks like i was wrong...
Okay, my posts are not always very long and pretty basic (so far), but that is the whole point of this blog; 'basic A-100 -news, -tips, -patches, sound-examples and other general (Eurorack analog modular) synthesizer info', for all modular synthesizer enthusiasts...

I found a good schedule to write now; when i am in the mood, a good part of my Sunday afternoons is spent on writing 2 or 3 posts and if there is any news (new video's / news from the forums / new thoughts) i try to fit them in between the 'regular' posting schedule.

The traffic-numbers are still going up, but slowly; I expect to reach 3000 page-views this or next month (was around 1700 last May, at the moment of my 100th post, and around 1000 in October last year).
The visitors come from 102 different counties, and it feels like my blog is slowly changing into some kind of Doepfer A-100 archive, which is also very cool.

I hope my numbers will keep on growing, but i'm not yet sure how to do that and where i could promote my site some more.
If you have an idea on how i could do this feel free to let me know, and feel free to let the whole world know about my blog... of course...
Spam it where you can ;-)

I must say i was very pleased to see Raul Pena's amazing A-100 tutorial video's popping up this summer.
Great video's that were very informative and clearer than i could ever have written for you in English.
It did save me the time to write about some hard to explain modules, like the A-188 for example...
Also check out his 12 days of Modular series HERE

So what can you expect in my next 50 posts?
I haven't even written about all the modules that i own, so you will see a bit more of that, even some more short reviews of the simple basic modules.
Sadly i don't have a big budget to invest in new modules at the moment.
A few more synth-books are on my book-shelf that i will write about.

Starting next year the CD-Tip section of the blog will include some more 'classic synthesizer albums', instead of the how-to-, sample- and more off-beat CD-tips i posted so far.
Although i am not a professional CD-reviewer i would like to let you know what CD's i find worth listening to.
Think of 70's and early 80's albums like "Cyborg" by Klaus Schulze, "Switched on Bach" by Wendy Carlos and Tomita's "Pictures at an Exhibition" or "The Planets".
I guess i should not name more now, but if you have any suggestions please leave a comment below.

Thank you all again for your feedback / re-tweets / +1's and Facebook likes so far.
I'm looking forward to write my next 50 posts...

(also check my 50th post from December 7, 2010,
                                          and my 100th post from May 22, 2011)

Booktip XI - Das grosse Buch zum A-100 Modular Synthesizer (in German Language)

A very interesting book by Andreas Krebs is almost out... although it is (still) only available in the German language.
The author has been working with analog (and other) synthesizers for around 30 years and has already written and maintained a pretty impressive blog.
His " Big Book to the Doepfer A-100 Modular-Synthesizer" will be available at the end of 2011/Now

In 320 pages he systematically goes through the most interesting modules in full detail and suggests unusual patches from his 'trick-book'
The book is illustrated with over 400 images, and a good read for not just Doepfer enthousiasts, it's a very nice book for analog synth enthousiasts too... 

It explains basic and some more difficult analog synth theory in a clear way.

Update 30/5.2025:

The book is out of print, but the author kindly offers it for free download:
http://www.a100.ideenhase.de/Krebs_Doepfer_A100_small.pdf.

Further information is available at www.ideenhase.de

A-130 + A-131 Voltage Controlled Amplifiers

A Voltage Controlled Amplifier ( VCA or variable-gain amplifier) is an electronic amplifier that varies its gain depending on an incoming control voltage (or CV).
It is one of the most basic building blocks for a modular synthesizer.
Find more on this on Wikipedia.
Modules A-130 and A-131 are very simple VCA's that can be found in most basic Doepfer systems.

For audio signals, you would normally use the exponential VCA (A-131), and for control voltages the linear VCA (A-130), but it doesn't always have to be that way, though.

The amount of amplification of the VCAs is determined by the voltage at the CV input and the position of the gain control, which sets the overall gain in the system.
The VCA has two audio inputs, each with an attenuator.
They are amplified by the combination of the gain and the two CV controls.

Remark:
The old versions of A-130/131 (those with CEM3381/CEM3382, which are actually 2 VCA's on one chip*) are not able to process slowly varying control voltages (AC coupled in/output).
The newer versions of A-130/131 (those with CA3080) are able to process even slowly varying control voltages (DC coupled in/outputs).

*it might be worth investigating these a bit more for a future DIY treatment

Most Wanted Update - MSY2 Module for A-100 System

Old Version of the MSY2,
the newer ones are in black

Great news...

It looks like the idea that i posted in December 2010 for some kind of extended version of an MSY2 module for the A-100 wasn't that bad.

In the Yahoo Doepfer A-100 Usergroup Dieter Doepfer recently announced that they "...are working on a modular version of the MSY2 with some additional features ( USB interface, several outputs with different clock dividing factors and polarity and some more )."

The MSY2 MIDI-to-SYNC/Clock Interface can be used to convert Midi clock into analog clock signals.

There is no release date or price available so far.

A-138 Linear/Exponential Mixer

Module A-138 is a simple four channel mixer that can be used for either control voltages or audio signals. (although i hardly ever use one for CV)
Each of the four inputs has an attenuator, and a master attenuator, so that the mixer can be used to interface directly with an external mixer, amplifier, etc.

There are two versions of this module:
A-138 a: potentiometers with linear response, especially suitable for control voltage mixing.
A-138 b: potentiometers with logarithmic/exponential response, especially suitable for audio signal mixing.

The latest version from April 2004 is an improved version of the module A-138b.
For the revised versions control In1 works as a DC offset generator (about 0...+5V) provided that no patch cord is plugged into socket In1.
If this feature is not required it can be deactivated by removing a jumper on the pc board.
In the summer 2004 the A-138a was introduced with this improvement.

In the summer of 2007 Doepfer also released a mix expander module A-138x, that increased the number of inputs of the A-138 by five.
That module was discontinued last year...

Sample and Hold with Doepfer A148 by Raul Pena

Raul Pena from http://raulsworldofsynths.com/ just posted a few new video tutorials.
Here are the first six (of seven!) in a series dedicated to Sample and Hold,Track and Hold, and comparisons with the two.

Video 1 : Track and Hold Vs. Sample and Hold with Doepfer A148 S/H
http://www.youtube.com/watch?v=KvjiKzBaTAs

" Demonstration comparing Track and Hold with Sample and Hold using the Doepfer A148.Sound and Video by Raul Pena."

All other A-148 video's after the break

Most Wanted VI - Special Vocoder MIDI-interface

I read the following text on one of Doepfer's A-129 vocoder system pages a long time ago, but it is still on Doepfer's website;

" A special MIDI-interface for the vocoder system is planned.

The basic functions are a 16-way CV-to-MIDI interface and a 16-way MIDI-to-CV interface (way 16 will be used for other functions like controlling slew-rate or voiced/unvoiced).

The CV-to-MIDI section converts the CV outputs of vocoder analysis into MIDI controllers which may be recorded by a computer sequencer. 

The MIDI-to-CV section converts incoming MIDI controller information into CV's for the vocoder synthesis section. 

Additionally we plan to store some factory and user definable 'vocals' in the MIDI interface so that you may call up complete vocals (like 'a', 'e', 'o', 's', 'sh' and so on) by MIDI program change events (may be we use another MIDI event type for this purpose). 

Thus the vocoder system will become a universal MIDI controlled filter system not limited to the standard vocoder features. "

Okay, i must say that it all sounds impressive and also very useful.
I do hope this module will be taken into production, but i believe this has been
on Doepfer's webpage for a while now, which makes me think that this module will probably never be made.
It might be in the Universal 12 bit AD-processor-DA module plans, because these things do need some processing power but i'm not so sure about that...
With all the announced features you could imagine this would not be a cheap module to make, but we'll see though...

Find more of my 'Most Wanted' posts HERE