Skip to main content

Filters VII: A-106-1 Xtreme Lowpass/Highpass Filter

The Doepfer A-106-1 Xtreme Filter was built as a kind of Korg MS20 filter clone.
The famous original MS20 included two filters: a 12 dB lowpass and a 6dB high pass filter connected in series both with a very special design.
On the A-106 product page Doepfer writes: " The A-106-1 is definitely not the right choice for "moogish" and "civilized" sounds but for extreme, exceptional and experimental sounds - this is why we call the module "X-Filter"... "

Doepfer found a way to use the same circuit simultaneously as lowpass and highpass for 2 different audio signals (a bit similar to the A-101-1 Steiner Vactrol filter that has even different audio inputs available, but with the special MS20 circuit).
For this two separate audio inputs for lowpass(LP) and highpass (HP) with separate level controls are available.
The sockets are normalled, so the signal applied to the LP input is available for the HP input too provided that no plug is inserted into the HP input socket.

The level control of the HP input is realized as a polarized input. This means that the signal can be added with the same polarity (+ range) or opposite polarity (- range) compared to the LP input.
This feature enables notch (+) and bandpass (-) filter functions too.

A lot of audio-examples can be found HERE
and on Andreas Krebs' blog

As you will hear in the demo's this is a very nice sounding filter with a distinctive sound.
It can sound very squelchy and dirty, and still also quite smooth...
If you are looking for a do-it-all filter, this might be the one you are looking for.
It is not my favorite filter, but i still rate it at 7/10...

Video:
Hans Richter - Rhythmus 23 - Figur 10 - KABELTON
http://www.youtube.com/watch?v=vNW6XXvJ74A

" ...just a test for something bigger... but i like it though.the sound was made with benjolin (rob hordijk and joker nies) and doepfer a-106-1."
Uploaded by Kabelton

Popular posts from this blog

DIY Modular Case Ideas

There are many ways to house your (eurorack) modular synth, i wrote about the pre-manufactured options from Doepfer earlier, find that post HERE, but of course you can also try to build you own case.
There are many ways to make your own A-100/Eurorack case if you start out with just the basic rails and busboard, and you can make it as cheap or expensive as you can.

Check out a few ideas;
Wooden cabinets and side-panels are still very popular amongst (modular) synth enthusiasts.
These simple case standards for the pre-manufactured LC9 cases are very simple, and can be sooo useful
http://synthesizerart.blogspot.com/2011/10/dual-doepfer-lc9-case-stand-v1-design.html Also check out the other great modular pictures on his site.
Matthew Goike (@Goiks) also has some nice wooden cabinets on display and for sale on his website: http://www.goike.com/node/5

...or do what Stretta did (or rather what his brother did), make a high-end wood/brushed aluminium cabinet with integrated LED-lights and some …

Doepfer A-150-8 Octal Manual/Voltage Controlled Programmable Switches Announced

Doepfer has just released some info on their new modules for NAMM 2017 (19-21 jan.) Besides some vintage editions of existing modules, the A-135ABC VC Performance mixer modules, the A-110-6Trapezoid Thru Zero Quadrature VCO and a new A-100LC1 case (economically priced small housing with 48 HP width) there was also one other interesting new module announcement:
Module A-150-8 contains eight manually/voltage controlled switches.  Each of the eight switches has a manual control button (Man.), a control voltage input (CV), a common Out / Input (O/I), and two In / Outputs (I/O1, I/O2).  The switches are bi-directional, i.e. they can work in both directions, so can connect one input to either of two outputs, or either of two inputs to one output. 
Two LEDs show which in / output is active (ie. which is connected to the common out / input).  In addition the LEDs are used for the programming of the module: For each unit the operating mode can be selected:  Toggle or Level controlled. In Toggl…

Happy New Year From PatchPierre

Hi there, it's me again... Happy New Year!

You might have noticed that I havent posted a lot in the last 2 years...
It's been a rough time for me since the sudden loss of two parents within a relatively short time-span and I really needed some time to get myself together... to set things straight, finding myself and selecting priorities... even my regular work suffered from this breakdown.

It took a while to understand it all, and to get a better grip on it, and it's sometimes still not very clear.
I think I have found a way to cope with most of it now... although the slight autism that I have (ADD-like) doesn't make it easy for, especially in crowds with lots of people I don't know...
On my journey I also (re-)discovered the beautiful woman that has always lived inside of me and that i need to accept and cherish... more on that maybe later... I'm not considering changing the name of the blog to PatchPetra.Net 😇 (...yet), but you might spot me somewhere at mod…