AMSynths Diode-1, semi-modular synth based on Roland System 101/102 modules

AMSynths Diode-1 is an upcoming semi-modular analog Synthesizer based on clones/replicas of the Roland System 101/102 modules.

Two years ago, Rob Keeble from AMSynths unveiled the Diode-1, a new semi-modular Synthesizer with circuits based on the Roland System 100. More precisely, these are features from the System 101 and 102.

At the Machina Bristronica event, the developer gave an update on the project. It’s still in prototype status, but the synth will be ready and available around Christmas for a very reasonable price of £300.

A very intriguing compact semi-modular synth with a reasonable price, just like AMSynth’s other modules. The first sounds are also already convincing.

Update from September 25, 2023

Here are new photos of the AMSynths Diode-1 Synthesizer, and the developer also published the full feature set.

Features

Envelope Generator – “traditional but fast” ADSR
LFO – with three waveforms (triangle, sine, sawtooth)
S&H – with its own wide-ranging clock (0.25Hz to 400Hz)
VCO – with range switch and four waveforms (triangle, sawtooth, square, pulse)
The VCO has the sync feature of the 102 (strong or weak)
Noise source with white and pink colours
Ring Modulator, normalized to the VCO and LFO
High-pass filter, 3dB passive design
Voltage-controlled 24dB diode filter with self oscillation
Voltage-controlled amplifier
Output stage that mixes a second input into a final output

Article September 21st, 2023

Vintage synthesizer clones/replicas are very trendy. Expensive or even affordable. There is something for everyone. AMSynths, led by Rob Keeble, made a name for itself, working with Behringer on the ARP 2600 replica and other projects.

In addition to helping with these projects, he also develops Eurorack modules based on classic synths. His latest project is the Diode-1, based on parts of the iconic Roland System-100.

AMSynths Diode-1

Diode-1 is a new semi-modular analog Synthesizer based on the circuits of the Roland System 100. But it is not a complete clone/replica. More precisely, Rob uses replicated/cloned elements from the Roland System 101 and 102 modules, expands on their features, and incorporates them into a new synth.

It features a single VCO with various waveforms (tri, saw, square, and pulse), pitch control, sync, PWM, LFO, and more. A white or pink noise generator and an external input are also onboard. All three signals can be adjusted in level in a dedicated mixer section with sliders.

There is also a ring modulator replicated from the Roland System 102 modules. It’s pre-connected internally to the LFO and VCO.

From here, it proceeds to the filter section, which consists of an adjustable high-pass and a low-pass filter with resonance. It’s based on a diode-based ladder circuitry and can be modulated with modulator, keybed, and ADSR signals simultaneously.

On the modulation side, you get an ADSR envelope, a single LFO, and an S&H generator, all based on the Roland System 102 module. Further, you have a VCA with a main output. The signal path is connected internally but can be modified via the built-in patch points.

You can’t see everything in the photo, but it appears to be a pure analog synth voice without MIDI or USB capabilities. So a Eurorack module that you can also screw into a case and use as a desktop synth.