MousePlugins has launched X-Or, a free monophonic bass synthesizer for Home windows and Linux.
X-Or is a two-oscillator synth with twin free-running noticed waves, a resonant low-pass filter, a filter contour envelope, a loudness envelope, and glide.
I like programming synths, however I hardly ever attain for devoted mono synths in my very own workflow as a result of I don’t make some of these bass and lead sounds that usually. If you happen to principally want basslines, sub layers, plucky leads, and pedal-bass elements, although, a restricted synth like this could make sense as a result of there’s much less to consider.
The essential structure is fairly easy. OSC A follows the incoming MIDI be aware, whereas OSC B will be offset with coarse and positive tuning. The OSC MIX management blends the 2, so you should utilize small detune quantities for beating, fifths for stabs, or octave offsets for thicker bass patches.
The filter is a resonant low-pass with its personal attack-decay contour envelope. CONTOUR controls how a lot the envelope opens the cutoff on note-on, then the cutoff falls again to its resting place.
There isn’t a separate filter maintain or launch, which, in my view, makes the synth higher fitted to plucky bass sounds than general-purpose monosynth use.
The loudness envelope can be fairly primary. You get Assault, Maintain, and Decay, with note-off utilizing the identical Decay time to return to zero. Smooth retriggering helps keep away from clicks when new notes arrive whereas the earlier tail remains to be audible.
X-Or is transposed down one octave by default for pedal-bass voicing, so middle-keyboard MIDI elements land in a decrease register. Glide is a pleasant addition for these acid basslines, and the timing goes from 0 to 2000 ms.
There’s additionally a dwell chart with Waveform and Spectrum views, plus output meters. Presets will be saved as .xorpreset recordsdata, and the plugin consists of A/B evaluate, copy/paste, undo/redo, manufacturing unit presets, and a resizable editor.
I examined X-Or briefly, and it really works positive right here. It sounds positive, too.
The half I’m much less positive about is the interface. I have no idea whether or not this plugin was AI-assisted or not, and the product web page doesn’t say both manner, however some UI particulars have that vibe-coded look to me.
For instance, some labels seem truncated with ellipses, like “Reson…” as an alternative of “Resonance,” and some interface borders really feel uneven while you look intently. That doesn’t show something concerning the DSP, after all. It might be that the developer can code a synth however used AI assist or different tooling for the interface.
That is the complicated half of the present plugin scene. If a free plugin works, sounds good, and is helpful, ought to we cowl it even when the presentation feels AI-assisted?
Or ought to BPB keep away from plugins like this completely until the developer is obvious about how they had been constructed? I’d genuinely like to listen to what readers assume.
X-Or is obtainable in VST3 and CLAP codecs for Home windows 10/11 and Linux x64. There isn’t a macOS model at launch. The plugin is free and doesn’t require activation.
Obtain: MousePlugins X-Or (FREE)
Deal of the day 🔥: EXCLUSIVE ROLAND SALE (as much as 80% OFF)!
Extra:
Final Up to date on Might 29, 2026 by Tomislav Zlatic.
