BlaknBlu - Oscar DSF Mk2

Oscar DSF Mk 2 is a dual stereo oscillator built around Discrete Summation Formulae — a synthesis technique that can generate many of the classic sounds typically associated with FM synthesis, but with a more direct, hands-on approach. Rather than wrestling with multiple carriers and modulators, you shape sounds through two main controls: Partials builds your sound from a pure sine into rich textures, while Mod Ratio — especially combined with the three-way Mode switch — defines how these harmonics play together. Switch between natural harmonic relationships or dive into more experimental territory.

Each oscillator runs through an FM-based wavefolder stage. While technically it's an FM operator with zero carrier frequency, what matters is how good it sounds. This clever design creates smooth folds that add richness rather than harshness, responding nicely to CV for dynamic textures or punchy bass sounds.

Mk 2 turns Oscar DSF into a true standalone voice. The internal VCA now has a separate attenuator for when you're using the Partials input, or you can drive it from a new dedicated CV jack with its own attenuator — a lot of sound in 10HP. And like the rest of the Mk 2 range, you can now switch to mono, which sums the two DSF oscillators and their wave folders. Beyond helping with mono workflows, tuning the two oscillators to interesting intervals in mono creates amazingly rich harmonics — because maths…!

Both oscillators follow the same pitch CV, but the second can drift up to an octave either way — great for subtle frequency beatings or dramatic stereo effects. A TUNE switch outputs a steady A440 reference tone for tuning other oscillators, or reads and holds whatever CV is present at the leftmost V/oct input.

A complete FM-flavoured voice that's more complex in theory but much more straightforward in practice :)

Features:

• Dual DSF-based stereo oscillator in 10HP
• Switchable mono summing mode
• FM-style sine wave folder per oscillator
• Built-in VCA with dedicated CV input and attenuator
• Three modulation modes: Free (F), Rational (R) and Irrational (I)
• Oscillator detune with ±1 octave range
• Auto-tuning function with A440 reference
• Dual function knobs with OSC/FOLDER mode switch
• Two V/oct inputs with attenuators
• Stereo pan CV control
• CV control over partials and wave folding
• Dual stereo outputs (L/R)