Drupiter Synth
Jupiter-8 inspired polyphonic/monophonic synthesizer
Drupiter Synth
Jupiter-8 Inspired Polyphonic/Monophonic Synthesizer
Drupiter brings the classic Roland Jupiter-8 sound to the Korg drumlogue with dual oscillators, a multi-mode filter, and comprehensive modulation capabilities. Now featuring polyphonic and unison modes alongside the original monophonic operation. Built on Bristol Jupiter-8 emulation, it delivers rich, warm analog-style tones perfect for bass, leads, pads, and more.
Features
🎹 Synthesis Modes
- Polyphonic Mode: 4-voice polyphony with intelligent voice allocation
- Unison Mode: Rich ensemble effects with golden ratio detuning and stereo spread
- Mono Mode: Classic monophonic operation with portamento/glide
🎹 Dual DCO Architecture
- 5 Waveforms per oscillator: SAW, SQR, PULSE, TRI, SAW_PWM (DCO1), SAW, NOISE, PULSE, SINE, SAW_PWM (DCO2)
- DCO-1 octave selection: 16’, 8’, 4’
- DCO-2 octave selection: 32’, 16’, 8’, 4’
- Pulse width control for dynamic timbres
- SAW_PWM: Pulse-width modulated sawtooth for evolving timbral character
- DCO2 fine tuning for thick, chorused sounds
- Oscillator mix with independent level controls
⚡ Modulation Synthesis
- Hard Sync: DCO2 syncs to DCO1 (OFF/SOFT/HARD modes)
- Cross-Modulation: DCO2 → DCO1 FM for complex harmonic content
- Variable amount controls for both effects
🔊 Multi-Mode Filter
- State-variable filter with resonance
- Keyboard tracking (0-120% adjustable)
- Envelope amount (±100%)
- Self-oscillation capability
📊 Dual ADSR Envelopes
- Filter Envelope: Controls filter cutoff modulation
- Amp Envelope: Controls voice amplitude
- Independent Attack, Decay, Sustain, Release for each
- Smooth exponential curves
🌀 Global LFO & Modulation Hub
- LFO Rate: 0.1Hz - 50Hz adjustable
- Modulation Hub: 18 modulation destinations including:
- Synth mode switching (poly/mono/unison)
- Unison detuning and stereo spread
- Envelope to pitch modulation
- Portamento/glide control
- Filter and amplitude modulation
🎛️ Effects
- Chorus/Space effects with dry/wet/both modes
- Stereo widening capabilities
Factory Presets
Drupiter includes 12 factory presets covering common synthesizer sounds:
| # | Name | Description |
|---|---|---|
| 1 | Jupiter Bass | Deep, punchy bass with filter envelope |
| 2 | Jupiter Lead | Bright, cutting lead with sync |
| 3 | Sync Lead | Hard-synced aggressive lead sound |
| 4 | FM Bell | Cross-modulated bell tones |
| 5 | Analog Pad | Warm, evolving pad with slow attack |
| 6 | Poly Arp | Bright arpeggiator-style sound |
| 7 | PWM Lead | Pulse-width modulated sawtooth lead |
| 8 | Unison Pad | Rich ensemble pad with golden ratio detuning |
| 9 | Poly Bass | Polyphonic bass with glide |
| 10 | ENV FM | Filter envelope modulating pitch |
| 11 | Stereo Unison | Wide stereo ensemble effects |
| 12 | Glide Lead | Smooth portamento lead sound |
Parameters
Drupiter has 24 parameters organized across 6 pages. Use the drumlogue’s page buttons to navigate.
Page 1: DCO-1 (Oscillator 1)
| Parameter | Range | Description |
|---|---|---|
| D1 OCT | 0-2 | Oscillator 1 octave (16’, 8’, 4’) |
| D1 WAVE | 0-4 | Waveform: SAW, SQR, PULSE, TRI, SAW_PWM |
| D1 PW | 0-100% | Pulse width (affects PULSE waveform) |
| XMOD | 0-100% | Cross-modulation depth (DCO2 → DCO1 FM) |
Page 2: DCO-2 (Oscillator 2)
| Parameter | Range | Description |
|---|---|---|
| D2 OCT | 0-3 | Oscillator 2 octave (32’, 16’, 8’, 4’) |
| D2 WAVE | 0-4 | Waveform: SAW, NOISE, PULSE, SINE, SAW_PWM |
| D2 TUNE | 0-100 | Fine tuning (-50 to +50 cents, 50=center) |
| SYNC | 0-2 | Oscillator sync: OFF, SOFT, HARD |
Page 3: Mix & Filter
| Parameter | Range | Description |
|---|---|---|
| MIX | 0-100% | Oscillator mix (0=DCO1 only, 100=DCO2 only) |
| CUTOFF | 0-100% | Filter cutoff frequency |
| RESO | 0-100% | Filter resonance |
| KEYFLW | 0-100% | Keyboard tracking (0-120%, 50=half tracking) |
Page 4: Filter Envelope
| Parameter | Range | Description |
|---|---|---|
| F.ATK | 0-100% | Filter envelope attack time |
| F.DCY | 0-100% | Filter envelope decay time |
| F.SUS | 0-100% | Filter envelope sustain level |
| F.REL | 0-100% | Filter envelope release time |
Page 5: Amp Envelope
| Parameter | Range | Description |
|---|---|---|
| A.ATK | 0-100% | Amp envelope attack time |
| A.DCY | 0-100% | Amp envelope decay time |
| A.SUS | 0-100% | Amp envelope sustain level |
| A.REL | 0-100% | Amp envelope release time |
Page 6: Modulation Hub
| Parameter | Range | Description |
|---|---|---|
| LFO RT | 0-100% | LFO rate (0.1Hz - 50Hz) |
| MOD HUB | 0-17 | Modulation destination selector |
| MOD AMT | 0-100 | Amount for selected modulation destination |
| EFFECT | 0-3 | Effect: CHORUS, SPACE, DRY, BOTH |
Sound Design Tips
Rich Bass Sounds
- Set DCO1 to SAW at 16’ (sub-octave)
- Set DCO2 to SQR at 8’ with slight D2 TUNE
- Adjust MIX for balance between oscillators
- Use filter with moderate RESO and KEYFLW
- Short filter envelope with positive amount
- Try the Jupiter Bass preset as starting point
Cutting Leads
- Use PULSE or SQR waveforms
- Enable SYNC (SOFT or HARD) for brightness
- Adjust MIX for oscillator balance
- Moderate filter envelope amount
- Use XMOD for harmonic complexity
- Check Sync Lead preset
Warm Pads
- Mix SAW (DCO1) and TRI (DCO2)
- Fine-tune DCO2 with D2 TUNE
- Adjust MIX for blend
- Long amp envelope A.ATK and filter F.ATK
- Use Analog Pad preset
Bell Tones
- Enable XMOD (cross-modulation)
- Use SAW or TRI waveforms
- Fast filter F.DCY to zero sustain
- Check FM Bell preset
Sync Leads
- Set DCO1 to SAW or PULSE
- Set DCO2 to SAW or SAW_PWM
- Enable SYNC (50-100%)
- Adjust MIX for oscillator balance
- Modulate filter with envelope
Installation
- Download
drupiter_synth.drmlgunitfrom the releases page - Connect your drumlogue to your computer via USB
- The drumlogue will appear as a USB drive
- Copy the
.drmlgunitfile to theUnits/folder - Safely eject the drumlogue
- Power cycle the device
- Navigate to the synth selection menu
- Select “Drupiter”
Technical Specifications
- Type: Polyphonic/Monophonic Synthesizer
- Voices: 4-voice polyphony + unison mode
- Oscillators: 2 DCOs with 5 waveforms each
- Filter: Multi-mode state-variable filter
- Envelopes: 2x ADSR (VCF, VCA)
- LFO: 1 global LFO with modulation hub
- Parameters: 24 (6 pages × 4 parameters)
- Presets: 12 factory presets
- Sample Rate: 48 kHz
- MIDI: Full note on/off with velocity
- CPU Usage: High (approaches drumlogue limits)
Credits
- Based on: Bristol Jupiter-8 Emulation
- Developer: CLDM (0x434C444D)
- Built with: Korg logue SDK
- Inspired by: Roland Jupiter-8
Download
⬇️ Download Drupiter v1.1.0
File: drupiter_synth.drmlgunit • Size: 31 KB
Documentation
- README.md - Detailed documentation
- UI.md - User interface guide
- RELEASE_NOTES.md - Version history
Support
Found a bug or have a feature request? Please open an issue on the GitHub repository.