System80 are sticking with their love of the Roland vibe and have released two new Eurorack modules. The 810 is a three-section subtractive synth voice and the 820 pulls out the VCO part to offer it up on its own.
It’s three modules in one; a VCO to VCF to VCA. There’s nothing particularly remarkable about that except that System80 do this stuff with such a high level of style and competence. The VCO has a choice of four selectable waveforms with pulse width modulation available on the pulse waveform. You don’t get individual waveform outputs, you have to make a choice and go with it. There’s a Sync input switchable between “Weak” and “Strong” and CV control over pitch and PWM.
The filter follows the Roland topology with 12dB and 24dB response. The output of the VCO is normalised to the input and there’s a second input that takes a sub-oscillator from the VCO. It has CV control over resonance, which can be pushed to self-oscillation, and two controls over the frequency; one unipolar and one bipolar.
The filter is then normalised to the VCA which has two additional inputs with attenuators.
The 810 reflects the 110 module from the Roland System 100m but looks about a thousand times more gorgeous. They say it also has elements from the System 700 and Jupiter-8 in there somewhere. It’s available now for $425.
The 820 pulls the oscillator out of the 810 but gives us all the waveforms on their own outputs. It’s based on the Roland style saw integrator and waveshapers and features a “discrete temperature compensated saw (ramp) core coupled to waveshaping circuitry that produces a pulse wave with adjustable width, a triangle wave and a sine wave. The conversion of the saw wave to a triangle wave produces a distinctive reset glitch at each peak. The triangle wave is bent by a diode shaper to produce an approximate sine wave.”
The 820 is available now for $220.
Both these modules are open source and you’ll find the design files on Github.