Cherry Audio PS-20 Review: Transform MS-20 Mono Synth to Poly Power

Unlocking Polyphonic Potential from a Mono Synth Legend

For decades, the Korg MS-20's aggressive filters and raw oscillators defined iconic mono synth sounds. Yet its monophonic limitation remained. Cherry Audio's PS-20 solves this creatively, transforming the MS-20 architecture into a versatile polyphonic instrument while retaining its sonic DNA. After testing this $29 plugin extensively, I confirm it delivers authentic character with expanded capabilities that modern producers need. Let's dissect why this isn't just another emulation.

Authentic MS-20 Foundation Meets Modern Flexibility

The PS-20 meticulously replicates the MS-20's signal path, from its distinctive high-pass/low-pass filter combo to the gritty oscillators. Crucially, Cherry Audio implemented two key enhancements that elevate this beyond nostalgia:

1. Poly/Mono Toggle Switch: Instantly transform from classic mono behavior to 8-voice polyphony. This isn't merely layered unison—it's true polyphonic playability.
2. Voice Allocation Controls: Adjust voice count (1-8) and engage detune-heavy Unison mode for massive sounds.

The semi-modular patching system mirrors the original's flexibility. Clicking the Focus button zooms into the cable routing area, where drag-and-drop connections enable complex signal flows. Reset instantly clears experiments—perfect for workflow.

Professional Insight: While the MS-20's filter resonance could sometimes thin out bass, the PS-20 retains low-end punch even at high resonance settings. This makes it exceptionally usable for modern basslines without EQ compensation.

Creative Workflow Features Beyond Hardware

Beyond sound, Cherry Audio addressed real producer pain points:

• Resizable Interface: Scale the GUI from compact to full-screen based on your monitor or workflow stage.
• Integrated Keyboard: Click the QWERTY icon for an on-screen keyboard—invaluable when inspiration strikes without a MIDI controller.
• Preset Diversity: 200+ presets showcase the range, from searing leads to evolving poly pads.

Transforming Sounds: Mono vs. Poly in Practice

The magic lies in dynamically switching modes during performance. Consider these applications:

• Bass & Lead Preservation: Mono mode delivers authentic, focused MS-20 aggression. Hear the bite in this bass preset:
• Polyphonic Textures: Engage poly mode for lush chords or sustained pads. Notice how polyphony transforms a simple sequence:
• Hybrid Articulations: Use mono mode for percussive pad "plucks" before switching to poly for sustained notes. This creates rhythmic interest impossible on the original hardware.

Beyond the Video: Advanced Sound Design Tips

While the video showcases presets, the PS-20 excels under deep customization:

1. Modulate Filter Mode: Assign an LFO to smoothly transition between high-pass and low-pass filters for evolving textures.
2. Patch External Audio: Process drums or vocals through the MS-20's legendary external signal processor (ESP) section.
3. Create Unison Stacks: Activate Unison mode with 4+ voices and subtle detune for supersaw-like thickness while retaining analog character.
4. Automate Mode Changes: Record live toggling between mono/poly within your DAW for dynamic arrangement shifts.

Industry Context: Competing emulations like Arturia's MS-20 V focus solely on mono reproduction. The PS-20's polyphony offers unique creative territory, making it a standout value at its price point.

Essential Tool Recommendations

• For Sound Designers: Pair with Cableguys ShaperBox 3 ($69) for rhythmic modulation of the PS-20's filters or amp envelope.
• For Mix Integration: Use TDR Kotelnikov (Free) to gently compress low-end-heavy patches without sacrificing punch.
• Learning Resource: Syntorial ($129) trains your ear to program the PS-20’s complex architecture intuitively.

Final Verdict: A New Classic Emerges

The Cherry Audio PS-20 achieves the remarkable: it honors the Korg MS-20's legacy while decisively solving its limitations. The poly/mono switching isn’t a gimmick—it fundamentally redefines the instrument’s creative scope. For under $30, it delivers professional-grade sound and innovative workflow enhancements. If you've ever craved the MS-20’s character without monophonic constraints, this plugin demands your attention.

Your Turn: When designing hybrid mono/poly patches, which parameter do you find most dramatically transforms the sound—filter resonance, envelope decay, or voice detune? Share your approach below!