UN/T-01, MICRONIX, and Colony: 3 Free Plugins Worth Grabbing This Week

Three plugins, three different jobs for your low end

This week's free-plugin crop lines up almost too neatly for a bass-focused producer: a drum machine with real 808 synthesis on the kick track, a monophonic synth built from the same open-source engine inside a Eurorack classic, and a six-effect utility box with a sidechain ducker built right in. None of these were released with "bass" in the pitch copy, but all three earn a slot in a low-end-heavy session. Here's what each one actually does, and where it fits.

UN/T-01 by All The Machines: an 808 drum machine that doesn't skip the bass drum

UN/T-01 is a free drum machine built around synthesized 808 sounds, with sample playback and a built-in step sequencer sitting alongside the synthesis. It covers six tracks — bass drum, snare, hi-hat, percussion, toms, and cymbal — plus extra percussion voices (clap, rimshot, claves, cowbell, maracas, and congas folded into the tom track). Each track can run its own synth voice or swap to a loaded sample.

The part that matters for bass work is the bass drum track itself. Most free 808-style machines treat the kick as decoration; UN/T-01 gives it Tune and Decay controls like the rest of the synth voices, which means you can dial the kick's fundamental to sit in your track's key instead of fighting it later with a pitch shift or a separate bass layer. That's a genuinely useful shortcut if you build sub-heavy tracks around a single low note anyway — tune the 808 to the root, and your kick and bass are already in agreement before you've touched a compressor.

The sequencer runs 16 steps (extendable to 32 across two pages), with per-track length from 1 to 32 steps, independent swing, and per-step velocity and decay. Euclidean generation, a randomize function, and a "Mutate" control for small pattern nudges make it fast to get a groove that isn't a straight 16th-note grid. There are 48 presets spanning electro, boom bap, house, techno, and drum and bass kits, which is a reasonable starting point if you want a reference for how the 808 track is usually tuned relative to the rest of the kit.

On the processing side, each track gets a distortion and reverb send, and the master section has a low-pass filter, compressor, and limiter sitting after everything. If you're running the 808 bass drum as your actual low-end source, that master low-pass is worth checking — it's easy to let it quietly roll off sub content you wanted to keep if you're not watching it.

UN/T-01 runs as VST3, AU, CLAP, and standalone on macOS 12+ (Apple Silicon and Intel), and VST3, CLAP, and standalone on 64-bit Windows. There's no account to create, but the download link is gated behind an email address on the product page — worth knowing going in, and the "send me updates" box is checked by default if you'd rather not get mailing-list traffic.

MICRONIX by Push and Groove: a free mono synth built on Plaits

MICRONIX is a free monophonic synth that runs on the open-source DSP code from Mutable Instruments' Plaits module — the same engine a lot of Eurorack users already know from the hardware. That means all 24 Plaits synthesis models are available inside a normal plugin instrument: virtual analog, FM, wavetable, granular, physical modeling, and percussion models, each mapped to the same three macro controls (labeled differently per model to match what they actually do).

Monophonic-by-design is exactly the constraint you want for a lot of bassline work — one voice, full attention, no accidental polyphony smearing a sub part. The amplitude section has a standard ADSR, plus a low-pass gate mode with its own Decay and Color controls, which is aimed specifically at short, plucked, percussive sounds — a reasonable fit for a tighter sub pluck rather than a sustained drone. Retrigger and legato modes, glide, and pitch bend round out the performance side, so slides between notes in a moving bassline are built in rather than something you have to fake with automation.

Modulation comes from a five-waveform LFO (including sample-and-hold, free-running or DAW-synced) feeding a four-row mod matrix with sources like velocity, mod wheel, and aftertouch, routed to pitch, engine macros, or other controls, each with bipolar amount. That's enough depth to build movement into a bass patch — a slow filter-style sweep via Timbre or Morph modulation, for instance — without needing a second device.

The honest caveat: this is the single-engine free version. MICRONIX Pro, a separate paid product, adds a second engine and polyphony. If you just want a focused mono bass voice built on a genuinely respected synthesis engine, the free version covers that job on its own — the Pro upsell is for people who want to stack engines or go polyphonic, not a missing piece you'll feel the absence of on a pure bassline patch.

Formats are 64-bit VST3 on Windows, and AU/VST3 on macOS (Intel and Apple Silicon) — no CLAP build yet. Like UN/T-01, there's no account required, but the download runs through a $0 checkout page that asks for an email address.

Colony by 13x Audio: six effects and a sidechain ducker in one box

Colony is a free multi-effect plugin built around six processors — called Cells — that all move together under a single ENERGY knob: DRIVE (five saturation/distortion types, from warm to hard clipping, with character, tone, and frequency-focus controls), MOTION (tremolo, auto-pan, filter sweeps, pitch wobble), SPACE (reverb), PUMP (ducking, synced to tempo or triggered by a sidechain input), WIDTH (stereo widening), and COLOR (lo-fi coloration).

PUMP is the one worth building a workflow around on a bass bus. It's a ducking effect that can either follow the host tempo or react to an actual sidechain input — meaning you can route your kick into Colony sitting on the bass channel and get a pumping duck without reaching for a dedicated sidechain compressor at all. It won't out-finesse a purpose-built compressor on transient response, but for a fast "does this bass get out of the kick's way" pass, it's a legitimate shortcut, especially combined with the Hear Original and Level Match options for comparing wet and dry levels honestly instead of just trusting your ears on a louder processed signal.

DRIVE is the other Cell that earns a spot on bass: five saturation flavors with a dedicated frequency-focus control means you can push harmonic content into a specific band rather than saturating the whole signal evenly — useful if you want upper-harmonic grit on a sub part without thickening (or thinning) the fundamental. WIDTH deserves the usual caution that applies to almost every stereo-widening tool on a low-end source: keep it conservative, or off entirely, on anything carrying true sub content, since a wide sub reads as weak or inconsistent on anything other than a pair of studio monitors.

Colony runs on macOS 11+, Windows 10/11 (64-bit), and Linux (glibc 2.35+), as VST3 on all three, AU on macOS only, and standalone everywhere. No CLAP build. The article covering the release states plainly that the download needs no account, email, or license key — the most frictionless of this week's three.

Takeaway

None of these three were built with "bass" as the headline, which is exactly why they're worth a look: an 808 drum machine that lets you tune the kick to the root instead of fighting it, a monophonic synth running a respected open-source engine with the slide and glide controls a moving bassline actually needs, and a sidechain ducker you didn't have to pay for sitting inside a plugin you'd reach for anyway. Grab whichever gap matches what your session is actually missing this week, and keep width and lo-fi coloring conservative on anything carrying real sub content — that caution applies regardless of which of these three ends up in your chain.

If you'd rather build free plugins into your own catalog than keep track of someone else's downloads, Low End Candy's own Ratchet and The Clap are both free, no email gate, and built with the same bass-first mindset as everything above.