Saturday, December 6, 2014

Korg Mono/Poly vs. EHX 8-Step Sequencer & Doepfer Modular Skiff (Youtube video)

Today I wanted to try out how I could spice up a simple 3-note arpeggio on my Korg Mono/Poly by sending some CV modulation to its filter CV input. So what you are hearing here is the Mono/Poly with its lowpass filter cutoff frequency being externally modulated by a small modular rig. I just added some delay and reverb from the Korg SDD-1000 and Dynacord DRP-20.




Running on its internal arpeggiator the Mono/Poly sends out a gate signal for every note. I took this gate signal and used it as a clock source to synchronize an Electro Harmonix 8-Step Program analog sequencer and a Pittsburgh Modular Cell 48 case with 5 Doepfer Eurorack modules.


Korg Mono/Poly

Electro Harmonix 8-Step Program Sequencer

Doepfer A-143-9, A-151, A-138m, A-133 and A-140

My latest modular acquisition is the Doepfer A-138m 4x4 matrix mixer. It really doesn't look flashy at all nor does it have a fancy name. But looks can be deceiving. This IS a highly versatile and mighty tool. What does it do? Well, the principle is simple: It has 4 inputs and 4 outputs. You can route any input (arranged in horizontal rows) to any output (arranged in vertical columns) with whatever level you like. One really useful feature is that you can set each output column to "bipolar mode", meaning you can turn each level knob to the center position for no signal or clockwise for positive and counter-clockwise for negative (inverted) signal. That's a great thing for CV signals, but you can also use it for audio signals for example in order to change the characteristics of a filter or for M/S processing of a stereo audio signal.
So here you can see (and hear) the A-138m in action. The A-143-9 VC Quadrature LFO is providing the Mono/Poly's filter with some nice audio-rate FM while the A-140 ADSR Envelope Generator modulates the amount of LFO signal going through the A-133 Dual VC Polarizer. You can clearly spot the effect of the ADSR in the youtube clip as it creates those "a-u" and "u-a" vowel sounds. The A-151 Sequential Switch is a real funky tool, too. It can be used to cycle through 4 independent signals by routing 4 inputs to 1 output or 1 input to 4 outputs at a time, making for some very interesting rhythmical modulations. You can use it both on CV and audio signals. Hey, you can even build a sequencer with it but I will go into this another time.
This skiff really is a fun little toolbox with lots of functionality in such a small space. Enjoy the demo!