Wednesday, July 26, 2017

Infusor Eurorack Sub-Mixer Demo

In this video I jam on the Eurorack w/ my new Infusor module. Infusor is a 10HP active stereo audio sub-mixer w/ 6 inputs. Wish you had more channels on your outboard mixer? This may be for you. Here's a breakdown of this mix...
Channel 1 - Basimilus in stereo from the EMW VC Pan
Channel 2 - My Transistor-80 Analog Percussion Module
Channel 3 - Tiptop Hats909
Channel 4 - Pittsburgh Synthesizer Box on bass
Channel 5 - unused.
Stereo Outs - going to Pittsburgh Outs module

Recorded direct to Tascam DR-5 through Mackie VLZ-802. I have sold my only available unit, I'll make a few more and have them available on soon. For more info check out

Sunday, July 23, 2017

Transistor-80 Analog Percussion Module Eurorack Demo #1

The Transistor-80 is an analog percussion module I designed as a lo-fi incarnation of those transistor-based CR- DR- and TRs from the circa 1980 era. It is thump-y, hiss-y, and it has those click-y pops and bacon sizzle sounds. Sports 3 sounds: Bass Drum, Snare Drum, and Hats. Bass has a tone control that controls the amount of sub frequency (you may hear a slight boom if you're wearing headphones) the other two sounds have decay controls. It has individual volume knobs for each sound, and a single output jack for the mix. In this video I am feeding trigger gates from the Malekko Varigate 4, and recording output directly to Tascam DR-5.

If you're interested in hearing more check out a track on Soundcloud I made using the Transistor-80.

More modules will be built completely by hand in small numbers, including PCB and face plate. Further details and availability can be found on Modular Grid

Monday, July 10, 2017

Korg MS-20 Teardown: Pulse Width Modulation Install

The vintage Korg MS-20 monophonic synthesizer comes with a pulse width knob, but no way to patch a modulation to it. In this video I teardown the MS-20, and install a Pulse Width Modulation routing.

My PWM will come from the MG/T.Ext circuit that is already present on the synth. 90% of the time I want to use the MG, AKA the LFO, to modulate the Pulse Width. So all I will do is add a small pot and current limiting resistor for routing the MG/Total circuit to the Pulse Width.

What about the other 10% of the time I don't want MG going to PWM? Well the MG is only normalled to the Total/External jack. If something is patched into the Total jack, it will override the MG and be routed to the new PWM pot. It behaves exactly the same way as the MG/Total pots for Pitch/HPF/LPF. Pretty sweet.

At the end of the video I patch various things to modulate the Pulse Width. Stay safe, don't electrocute yourself, and be sure to unplug the synth at all times while doing work inside the unit.

Wednesday, July 5, 2017

Analog Drums Development Prototype

I've been developing a eurorack analog drum kit for some time. It's inspired by the sound of simple machines like the Boss DR-110 and the Roland TR-606. It's a basic kit made of of Bass Drum, Snare Drum, and Hi-Hat. The Hi-hat has a choke gate, so it can behave open/closed using a single voice just like a real drum kit. All 3 voices summed to a single output. It will have controls for independent voice levels, bass drum tone, snare decay and hat decay. I think you will want kill switches for all incoming gates as well. I am looking into how to integrate an accent trigger pulse as well.

In this video I audition some sounds using the Beatstep Pro as a clock, Varigate 4 for the gates, and nothing else. I didn't use a digital recorder this time, I'll save that for when the module is completed.
I added a quick soundcloud demo