A tiny console of painted metal and glowing lights, this instrument looks like it fell out of a vintage broadcast studio and onto your synth desk. Behind that playful, retro face is a serious, all‑analog engine, hand‑crafted in Brazil by Arthur Joly in very small numbers.
Mutuca FM is a monophonic desktop synthesizer built around two CEM3340 voltage‑controlled oscillators feeding a 24 dB/octave matched‑transistor low‑pass filter, VCA and ADSR envelope. Each oscillator offers independent waveform selection, with saw, triangle and pulse options you can switch into the signal path. The second VCO can act as a dedicated sound source, lock to the first via sync for sharpened harmonics, or become a modulator for FM tones that range from subtle animation to metallic bite. A front‑panel control lets you dial in modulation from VCO2 or from the envelope, and a switch lets you drop VCO2 down into LFO territory when you want slower, more dramatic sweeps.
Performance is immediate and tactile: a compact push‑button keyboard gives you two octaves of notes directly on the panel, while MIDI input on the rear lets you control the synth from a larger keyboard or sequencer. Cleverly, each oscillator can be switched to follow either the onboard keys or incoming MIDI, making quick splits and layered tricks possible without any menu‑diving. Audio exits through the VCA into a prominent analog VU meter that bounces with your patches, giving you level feedback as well as visual charm.
There are no patch memories, no menus and no hidden functions—Mutuca FM is a pure, direct analog voice designed to be played, tweaked and recorded in the moment. With production discontinued and only a small number ever built, it has the feel of a personal studio secret: a compact, expressive FM‑capable monosynth that wears its hand‑built character on every knob and switch.
