4ms Modules
Not one product but a house philosophy: compact, concept-driven Eurorack that treats timing and synthesis as problems worth solving differently.
Overview
Ask a rack owner what 4ms makes and the honest answer is "a lot of things that don't fit the categories." The company's own framing calls these compact, concept-driven Eurorack modules that often blur functional categories, and the catalog bears that out. The Dual Looping Delay packs two channels of clock-synced looping delay into a single panel and holds at least three minutes of audio across them. The Ensemble Oscillator takes what the documentation calls an unorthodox approach to synthesis. It uses 16 sine-based oscillators that enable additive synthesis with user-defined scales. The Atoner does something stranger still - it hijacks and distorts note timing rather than playing traditional sequences.
A player shopping 4ms isn't buying a voice or a filter. The clock is as much an instrument as the oscillator. The recurring "Ping" input, used across multiple modules to sync or trigger behavior, ties the family together more than any shared circuit topology does. Patch a clock into one module and the logic ripples outward.
The range also runs from the nearly invisible to the indispensable. The EnvVCA, released in 2023, is an 8HP analog module combining envelope, LFO, and VCA functions with a clean exponential response. It's the kind of utility you stop noticing because it simply does its job. The Rotating Clock Divider has been available since 2012 and dynamically rotates clock divisions across eight outputs, which is why it keeps turning up in rhythmic patches a decade on.
Key Features
Two Channels of Clock-Synced Looping Delay
The Dual Looping Delay is the flagship for anyone who thinks of delay as a compositional tool rather than an effect. Two independent channels of clock-synced looping delay, holding at least three minutes of audio between them, means you can capture a phrase, let it run against a clock, and layer something new on top without the whole thing drifting. Owners report the sync behavior is the draw—this is a delay that wants to be told what tempo to live at. It's also a module with a public life: firmware version is checkable through a system menu, and the source code is hosted publicly on GitHub, which tells you something about how 4ms regards the people who buy its gear.
16 Sine-Based Oscillators and User Scales
The Ensemble Oscillator confuses people on first patch and converts them on the second. Sixteen sine-based oscillators, bound to intervals of a scale you define, let you build chords and clusters additively rather than by stacking voices the conventional way. Because the scales are user-defined, the harmonic territory is yours to map. The module doesn't insist on equal temperament or anything else. The documentation calls it an unorthodox approach to synthesis, which is a polite way of saying it doesn't behave like the oscillator you already own.
Timing as a Playable Parameter
Rather than playing traditional sequences, the Atoner hijacks and distorts note timing. It pushes events off the grid and stretches the space between triggers, so rhythm itself is the material. It's sold two ways: as a kit for $125 or pre-assembled for $275.
Envelope, LFO, and VCA in 8HP
The EnvVCA, released in 2023, is the quiet workhorse of the lineup. It's an 8HP analog module that combines envelope, LFO, and VCA functions with a clean exponential response. It's the module you patch when you need movement without menu-diving. The exponential response keeps a swell sounding musical rather than mechanical, and players reach for it as a modulation source as readily as a dynamics stage.
Rotating Clock Divisions Across Eight Outputs
The Rotating Clock Divider, available since 2012, produces divided clock tempos from a single input and dynamically rotates those divisions across eight outputs. Instead of a static division sitting on one jack forever, the pattern shifts, so a patch that sounded locked starts breathing on its own.
Historical Context
The dates that survive in the documentation are sparse. The Rotating Clock Divider has been available since 2012, which places it among the modules that established 4ms as a timing-focused builder. The EnvVCA arrived in 2023, more than a decade later. One is a clock utility, the other a three-function analog channel. The MetaModule was noted in 2024 as a platform for running VCV Rack plugins in hardware and for building custom synths or effects, though no pricing or availability details are confirmed. The Ping input, a sync-and-trigger concept, recurs across multiple modules.
Collectibility & Value
The Ensemble Oscillator launched at $299, and the Atoner sits at $125 as a kit or $275 assembled. The MetaModule's pricing and availability remain unconfirmed according to the 2024 note, so anyone chasing one should verify before committing. User reports indicate occasional boot issues with the Dual Looping Delay, though the same players recommend it for its performance. A bundled eBay listing pairing a Synthwerks PC5V with a 4ms and Intellijel buff mult turned up at $175, but that's a package deal, not a benchmark for any single module. Beyond the DLD boot note, documented failure and repair information is thin, so buyers should expect to evaluate individual units on their merits.
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