idyllm modular

Patch Diagrams for Mermaid

idyllm — Sat, 16 May 2026 05:49:25 +0000

Patch Diagrams for Mermaid

Now for something different: progress on new modules has been slow in the new year, but I've been working on a tool to help diagram some of the patches that I've been experimenting with. Based on the Mermaid syntax, the mermaid-patch extension let's you embed patch diagrams in a page and it should be compatible with Material/MkDocs (which I use for this site).

39C3 Building Hardware Talk

idyllm — Mon, 19 Jan 2026 18:42:18 +0000

39C3 Building Hardware Talk

A nice talk by Kliment at 39CC showed up in my feed recently: Building hardware - easier than ever - harder than it should be. I thought that the speaker did a good job of summarizing what has changed in this space in the last decade or so, and how amazing that is when it comes to making DIY electronics acccessible.

2025 Year in Review

idyllm — Mon, 19 Jan 2026 18:34:11 +0000

2025 Year in Review

Time for a reckoning. After discovering this little corner of the universe a couple of years ago and getting some of the basics in place in 2024, I set a goal for 2025 to build a new module every two months. I figured that this would get me to the point where I had the core of a basic synth: VCO, envelope, VCA, VCF, and maybe couple of extras. Results and stats below the fold.

State Variable Filter

idyllm — Fri, 02 Jan 2026 19:50:33 +0000

State Variable Filter

The last module for 2025! At the beginning of the year, I had a goal to build a new module every two months with the objective of having the core of a synth by the end. With this filter, I think that the basic pieces are in place (although I still have lots of ideas for 2026). The state variable filter is a very elegant textbook design that translates nicely into an analog circuit. The prototype came together well and the filter response fits the theory beautifully. However, there was one issue...

More Modules

idyllm — Mon, 29 Dec 2025 18:51:54 +0000

More Modules

Taking advantage of some free time during the holiday, I've ported over the docs for another pair of modules that I built and installed a while ago: Random Noise and the '398 SNH.

ADSR Envelope Generator

idyllm — Sat, 27 Dec 2025 18:14:41 +0000

ADSR Envelope Generator

I recently got PCBs back for the second iteration of the ADSR envelope generator. I was originally inspired by the designs that Rene Schmitz published, which have their origins in a 555-based circuit by Johnathan Jacky (see the notes in the YuSynth version). The 555 core is very clever and encapsulates the state logic in the 555's internal latch and threshold circuits. I've gone through a few iterations to get to this version, but I think this one is really solid and adds something new (at least as far as I can find for the 555-core circuits): a trigger. More below the fold.

Updated Gate Delay

idyllm — Sat, 27 Dec 2025 17:18:27 +0000

Updated Gate Delay

After getting the PCBs back for the first version of the gate delay, I decided that there were two features I missed: split controls (CV and pot) for the delay itself and a trigger (short pulse) output.

Linear to Exponential Conversion

idyllm — Wed, 10 Dec 2025 01:29:30 +0000

Linear to Exponential Conversion

A couple of designs now have required linear to exponential conversion for the control signal, so I've added it as my first "building block" note in the reference section. This version is the one of the more sophisticated ones, including buffering and temperature compensation, so it's suitable for designs requiring V/oct tracking.

Dual Gate Delay

idyllm — Wed, 05 Nov 2025 01:47:54 +0000

Dual Gate Delay

When I started on the ADSR, I looked at a few commercial examples in addition to the DIY versions. While watching a couple of Monotrail Tech Talk videos (part 1 and part 2 - highly recommended!), the Erica Synths Black DADSR EG caught my attention with some interesting extras, and one of those was the delay.

Mixer+

idyllm — Sun, 12 Oct 2025 19:17:13 +0000

Mixer+

Continuing on the migration and clean-up of my modules, I refreshed the Mixer+ design and documentation. This was a more involved effort: I populated a second copy of the v1.1 PCB for my "production" case, and while I was doing that I ran into some issues.

Output Module

idyllm — Sat, 04 Oct 2025 01:37:02 +0000

Output Module

I've started to migrate the projects I've completed so far over to this site. The first one I ported is the output module.

Welcome

idyllm — Fri, 03 Oct 2025 23:53:37 +0000

Welcome

Have to start somewhere.