KORG monotron DUO - Portable analog synthesizer with dual VCO, X-MOD and filter MS-20/MS-10

KORG monotron DUO - Portable analog synthesizer with dual VCO, X-MOD and filter MS-20/MS-10

The Korg monotron DUO brings analog synthesis to a truly pocket-sized format. It incorporates two independently tuned analog oscillators (VCOs) and an X-MOD (cross modulation) circuit inherited from the classic Korg Mono/Poly to obtain everything from rich vibratos to extreme metallic tones. Its ribbon keyboard includes a Scale Selector (Chromatic, Major, Minor or Off) to play musical phrases with ease. Completing the set is an analog filter (VCF) based on the legendary MS-10/MS-20, AUX input for processing external sources, headphone output and built-in speaker , all powered by 2 AAA batteries with an approximate battery life of 8 hours.

Operation is direct and tactile thanks to its dedicated controls: VCO1 Pitch , X-MOD Int. , VCO2 Pitch , VCF Cutoff , VCF Peak and Standby/VCO1/VCO1+2 selector . The DUO’s sonic space lends itself to both crunchy basses and sharp leads as well as noise and drone effects. Via the AUX input (3.5 mm stereo mini jack) you can link drum machines, synthesizers or players and filter them with the VCF MS, while the headphone output (3.5 mm) allows you to practice or record silently; connecting headphones deactivates the internal speaker. The ultra-compact chassis ( 120 × 72 × 28 mm ) and its weight of 95 g make it easy to always have it with you.

Main features

• Dual VCO + X-MOD: Two analog oscillators with independent tuning and Mono/Poly-inspired cross modulation .
• Korg Classic Filter: Analog VCF taken from the MS-10/MS-20 for aggressive and characterful sweeps.
• Ribbon with Scales: Ribbon keyboard with Scale Select (Chromatic, Major, Minor, Off) for precise playing or sliding musically coherent phrases.
• External processing: AUX input to insert audio before the filter and shape other sources.
• Simple connectivity: headphone output, built-in speaker and headphone volume control.
• Pocket size: 120 × 72 × 28 mm; 95 g (without batteries); 2 x AAA batteries with approx. 8 h battery life.

Product benefits

• Instant creativity: straightforward controls without menus; perfect for learning and experimenting with analog synthesis.
• Sound with personality: The MS Series VCF and X-MOD deliver everything from warm tones to crunchy, metallic textures.
• Portable Versatility: Battery-operated, with built-in speaker and headphone output for use anywhere.
• Quick integration: Process your drum machine, synth, or player via AUX and add analog filtering instantly.

Use cases

• Mobile sound design: creating bass, leads, and effects on the move.
• Live and jam sessions: real-time textures and filter sweeps from the ribbon and X-MOD.
• Color Processor: Use the AUX input to give “MS character” to external signals.

Frequently Asked Questions

What scales does the selector include? Chromatic, Major, Minor, and Off (no scale quantization).

Can it be used as an external filter? Yes. The AUX input inserts audio before the VCF, allowing you to filter other sources.

Does the speaker always play? No. When you connect headphones, the internal speaker is automatically muted.

Description for projects

Korg Monotron DUO synthesizer: analog; synthesis structure: 2 VCOs with X-MOD and 1 VCF (MS-10/MS-20); controls: VCO1 Pitch, X-MOD Int., VCO2 Pitch, VCF Cutoff, VCF Peak; switches: Standby/VCO1/VCO1+2 and Scale Select (Chromatic/Major/Minor/Off); controller: ribbon keyboard; connectivity: 3.5 mm stereo AUX input and 3.5 mm stereo headphone output ; internal speaker switched for headphones; power supply: 2×AAA (autonomy approx. 8 h); dimensions: 120 × 72 × 28 mm; weight: 95 g (without batteries); includes AAA test batteries and manual.