Friday, 28 May 2021

Passive Modules

Finished guys
It looks like it has been a year since I built my last DIY module.
Time for some passive modules I guess.

I ordered two 2-hp blank.  I needed another multiple to fill the rack and I decided to experiment with some passive functions.


A passive multiple is very basic.  You simple connect the tip and ground of each jack.  In practice the ground connection is established via the aluminium panel.  No need to use wire.

The main difficulty here is at 2-hp, or a bit more than 1 cm width, you do not have a lot of margin to drill your holes.  You do not want the body of the jack to go over the edge.
Not perfect but good enough.
I used mostly very cheap jacks I got a long time ago, except for the one with the switch as the switch on the cheaper ones is really terrible.

Behind the scene



Bob at work with the panel
I also experimented with some minimal panel marking by using my Dremel to carve some traces and fill them with a permanent marker.  This should not age very well. Time will tell.

The second module is the combination of a passive OR and a half-wave rectifier, ideal to combine gates and manipulate control voltages or distord audio.  You’ll find  the layout for both of them at the end of the article.  I got the schematics from unrecordings! blog

In the rack

In the following piece, the Korg SQ-1 produces two tracks of gates and CV for the kick and hi-hat.
I used the multiple to distribute the gates everywhere in the synth and I used the OR function to build a third melodic track from the first one and the output of the Turing Machine,  clocked by the second track.  I know it sounds complicated.  Patch schematics is at the end of the article.
The half-wave rectifier produces some overtones to spice up the sounds.
The variations in the piece is me playing with the sequencer.


Connection layout


Patch of the day