HY Plugins have released HY Mono, a free monophonic synthesiser based on the Oberheim SEM with enough customisation to keep you playing for days.

HY Mono features two VCO units that can generate saw and pulse waveforms and a Sub/Noise unit. There’s also an LFO unit that can generate sine waveform.

You can download the synth plugin for free here: hyakken.moo.jp/WordPress/product/hy-mono

It features a massive number of effects and parameters to tweak your sound to exactly what you’re after, including:



Frequency: Bigger knob = coarse (range: -24 to +24 semitones)
Smaller knob = fine (-3 to +3 semitones)

Modulation: Frequency or Pulse width of oscillator can be modulated by envelope/lfo

Pulse Width: Set pulse width of pulse waveform (no effect on saw waveform)

Sync: Turn on sync button, oscillator of VCO2 will be synced to oscillator of VCO1

Sub: Select waveform of Sub oscillator

Mixer: You can control oscillator volume in VCF panel



Frequency: Cut-off frequency

Resonance: Resonance level

Modulation: Modulation depth (-100 to 100%)
Modulation source = Env2/LFO

Filter Type: You can control the balance of the lowpass and highpass
Turn on “BP” button, filter output switch to bandpass

Mixer: You can control outputs of VCO section by three knobs at the bottom of the VCF panel



ADSD type envelope generator
Release rate is defined by decay value

Velo to Envelope: Tick the velo box, envelope outputs will be affected by velocity input



LFO unit can generate sine waveform

Rate: LFO speed (0.1 to 55 Hz)

Phase: Phase position of sine waveform
This setting makes sense when “LFO Reset” switch is active



Time: Delay time
Turn on “S” switch, delay time is synced to host BPM

Mod: Delay time can be modulated by ENV1/LFO

FB: Feedback level

HP/LP: One pole filters for delay line outputs

Mix: Mix level of delay effect outputs to main signal path



You can control panning and master output level here

PitchBend Range


You can set PitchBend range here (+/-1 to +/-12 semitone)

Note Priority


If multiple notes are pressed at the same time one of the pressed notes will be given priority based on this setting

Control Modes


Re-Trigger: If this switch is ON, Env1 and Env2 are always triggered by key press

Filter Track: If this switch is ON, filter cutoff frequency will be affected by played note

LFO Reset: If this switch is ON, phase of LFO will be reset by key press

MIDI to Synth Parameters


You can modulate synth parameters by MIDI signal

Source Menu: Velocity, ModWheel, AfterTouch, CC1, CC2

Target Menu: VCO1 Freq, VCO2 Freq, VCF CF, VCA Amp, Pan, Delay Time

Knob: Mod depth (-100 to +100%)



You can transpose incoming MIDI notes (-2 to +2 octave)



ON/OFF Switch: Portamento on/off

Knob: Portamento time

Randomize settings


Ticked panels will be included randomize
In this case, parameters of VCO1, VCF, ENV1, and LFO will be randomized