VST Instruments

Onsen Audio – OS-251

OS-251

size 2 MB  / 7 MB  / 4 MB

OS-251 is a pure digital lo-fi synthesizer.

OS-251 is a “JUNO” style digital subtractive synthesizer with a simple yet powerful DSP algorithm. Unlike other plugins that use analogue simulation, OS-251 uses digital algorithms to give warm, lo-fi sounds.
The design of the oscillators and the selection of parameters were influenced by the JUNO-106, making it easier to express a thicker, chunkier sound.


The oscillator has alias noise (specific to digital signal processing) famous on classic samplers like E-mu SP-12 which adds lo-fi feeling to the sound. You can enjoy the powerful sound at modern sampling rates with your DAW.

  • Up to 10 voices of polyphony.
  • Oscillators (Sin, Square, Saw), with Shape parameter.
  • Square sub oscillator.
  • Noise oscillator.
  • Biquad low-pass filter (LPF) with Frequency and Resonance parameters.
  • Biquad high-pass filter (HPF) with Frequency parameter.
  • Envelope generator which can control LPF and amplitude.
  • Low-frequency oscillator (LFO) which can control LPF, amplitude, and Shape parameter.
  • LFO sync.
  • Chorus.
  • Flexible pitch controls (pitch bend width, octave, semitone, fine tuning).
  • VST3 / AU.

ttps://onsenaudio.com/

OS-251-Windows  ( 2 MB )

OS-251-macOS  ( 7 MB )

OS-251-Linux  ( 4 MB )

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