Mutable Instruments Marbles

Mutable Instruments Marbles is a random sampler — a source of controlled randomness for gates and voltages. Unlike pure noise, Marbles lets you dial in probability, repetition, scale quantization, and correlation, producing randomness that remains musical.

Two Sides of Randomness

The module divides into two independent sections. The t section generates random gates and rhythms from three outputs: t1 and t3 provide complementary gate patterns while t2 outputs the main clock or its random variations. Bias controls the probability of gates firing, Jitter adds timing variation from tight quantized rhythms to drunken swing, and the rate knob sets master tempo (or follows an external clock).

Melodic Randomness

The X section generates three random voltages: two smoothly varying and one stepped. Spread controls the voltage range from narrow intervals to wide leaps. Steps determines whether new random values are generated or previous ones are recycled — at full CW, it locks into a repeating sequence. The Scale buttons quantize output to musical intervals, with six built-in scales plus the ability to program custom scales from a keyboard or sequencer.

Déjà Vu

The central Déjà Vu control is Marbles' defining feature. It acts as a probabilistic loop — turning it up increases the chance of recycling previous random decisions rather than generating new ones. At noon, patterns half-repeat with variations. Fully clockwise, sequences lock into perfect loops. This single control transforms pure randomness into structured generative music that feels composed rather than chaotic.

Who Is This For?

Marbles suits modular users who want musical randomness:

• Generative composers building self-playing patches that evolve over time
• Live performers adding controlled variation without losing musical coherence
• Sound designers creating evolving modulation and melodic textures
• Mutable Instruments collectors seeking discontinued modules
• Modular beginners wanting an immediately inspiring random source

For pure random, simpler noise modules work. For randomness that feels musical and controllable, Marbles is the benchmark.