Every producer who's ever loaded an acid preset knows the sound and half of them have never touched the thing that makes it. Michigan Synth Works is trying to fix that. The MSW-820S, shown at Knobcon this past weekend, is their MSW-820 analog synth with a TB-303-style step sequencer built in.
## What it is Two analog oscillators, saw and pulse with a mix fader each, 4-foot to 16-foot range switches, sync, and pulse-width modulation. The filter is the 16-mode design from the 820, which itself descends from Roland's 1983 CMU-10. What's new is the sequencer: it runs the company's open-source SuperOS-303 firmware, so you get the slides and accents that make a 303 line move, plus pattern undo and redo, randomize, scale locking, triplet modes, and a web editor. USB-C power, MIDI, volt-per-octave, sync24, and two CV outs so it plays with a modular rig or a drum machine.
## What it costs Nothing announced. The current MSW-820 is $549 as a desktop unit and $499 as a Eurorack module, and Gearnews expects the S to land above that in both formats. Knobcon, in Chicago, is where small American builders show first; retail usually follows in a few months.
## Why it's a beat-business item 303 slides are all over trap and drill, usually as a sample or a plugin. A hardware sequencer forces you to write the line the way the original acid records were written: step by step, accent by accent, with your hands. That's a different bassline than the one you'd draw in a piano roll. If your 808 needs a friend, this is the one.
## Sources - Synth Anatomy, Sept. 2026, Michigan Synth Works MSW-820S: analog synth with 16-mode filter and TB-303 sequencer: https://synthanatomy.com/2026/09/michigan-synth-works-msw-820s-analog-synth-with-16-mode-filter-and-tb-303-sequencer.html - Gearnews, Michigan Synth Works MSW-820S is a dual-oscillator mono synth with a TB-303 sequencer: https://www.gearnews.com/michigan-synth-works-msw-820s-synth/ - Michigan Synth Works, MSW-820 product page: https://michigansynthworks.com/products/msw-820-analogue-synthesizer

