birdkids The Bateleur Eurorack VCO Module (MKII) plus expander

A discrete, fully analogue oscillator from Vienna's Birdkids, long discontinued and increasingly hard to find — especially paired with its expander, which went out of production earlier than the main module. The core is a discrete transistor sawtooth design with genuinely good temperature stability, and it sounds it: thick, forward, closer to the Moog end of the spectrum than the clean-and-clinical modern school. Four classic waveforms (sine, triangle, saw, pulse) plus a separate sub output, manual and CV pulse-width modulation, a smooth stepped range switch, ±7 semitone fine tune, and portamento glide.

What makes the Bateleur unusual is that the 4-pole low-pass filter isn't an afterthought — it tracks 1V/Oct, self-oscillates, and the VCO's pitch input is normalled to the filter's cutoff CV, so the two behave as a coupled pair rather than two separate blocks. That makes the filter a genuine second oscillator for FM work and a waveshaper for the main core. Thru-Zero FM is on board and is where the module gets seriously wild.

The Expander opens up what the main panel only switches: a proper resonance control instead of the on/off self-oscillation switch, an extra cutoff CV input, exponential FM with attenuator, and access to the built-in VCA with level control and attenuated CV input — turning the pair into a complete VCO–VCF–VCA voice in 30HP. It's a passive expander, connected by ribbon to the main module, drawing no current of its own.

Condition: good, with honest cosmetic wear. The panel finish shows scuffing and light marks around several of the knob collars and near the mounting holes — visible in the photos. Electronically all good: every knob, switch and jack works as it should, tested and working. Serial no. 256. Includes the original Birdkids box, the original "Voltage Controlled Oscillator" hangtag, both ribbon cables (power and expander link), and mounting screws.

Specs: VCO 22HP, 38mm deep, 100mA. Expander 8HP, 20mm deep, no current draw.

Shipping from the Netherlands, tracked. Offers welcome.