Music Instinct released Mi-03 Bassline, a free synthesizer plugin that revitalizes the classic 303 sound.
Few synthesizers have the same sort of fame and renown as Roland’s TB-303. Like it or not, it’s carved out a place in the likes of techno, trance, house, and even some of Massive Attack’s output.
That said, you can ask 20 people what their favourite VST emulation is for the 303 and get 20 different answers. I typically use D16’s Phoscyon, but I always take a look at free emulations.
Mi-03 Bassline is one such instrument, and it goes a bit further than some of the 303 emulations you’ll see in the land of free software.

One of the big things to note is that Mi-03 moves away from programming sequences in the 303 like you would on the hardware. Sure, that’s a fine way of doing things if you have a vintage unit, the Behringer TD-3, or any number of clones that have sprung up since Roland stopped manufacturing them.
However, that isn’t the way to do things with a keyboard and mouse. Thankfully, the sequencer here is more visual, allowing users to readily program acid sequences as needed.
The core sound behind the plugin is good as a whole. When paired with a good distortion and delay, you’ll be hard-pressed to find fault. Granted, if you own the original hardware, you likely will.
Mi-03 doesn’t stick solely to the sound shaping parameters of the TB-303.
For starters, as opposed to just attack and decay, the envelope has a sustain and release stage. Waveforms are a bit different as a whole too, with a saw, square, and pulse wave all being selectable.
It does feature a built-in distortion, but I often skip right ahead to throwing Thermal on things like this to coax out that acid sound.
As a free instrument, I don’t think Mi-03 has many equals. Sure, TAL’s Bassline still exists, but good luck getting that running on a Silicon Mac.
If you’re after a slice of a more authentic acid sound, Mi-03 might be for you. It is pay what you want, so kick a few bucks the dev’s way if you can.
Download: Mi-03 Bassline (FREE / Name-your-price)
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