BASTL Instruments Ikarie Stereo Filter

Bastl and Casper Electronics have teamed up again to create Ikarie — a richly featured, characterful dual filter module that excels at spatial modulation, stereo imaging, and dynamic filtering. Drawing inspiration from classic state-variable designs and experimental processing techniques, Ikarie blends analog warmth with clever control schemes in a highly playable 14HP format.

At its heart are two parallel 12dB/oct state-variable filter cores, one for the left channel and one for the right. These can operate independently or in unison, with the unique filter mode control sweeping between lowpass and highpass, making bandpass behaviour easy to access without mode-switching. The filters respond beautifully to pinging, with different flavours available depending on whether you use the Left, Right, or Beyond output — the latter providing the spectral difference between the two cores, effectively turning Ikarie into a twin-peak or band-reject filter.

But filtering is just the start. Ikarie includes a voltage-controlled stereo VCA on the output and an internal envelope follower with three decay settings, enabling automatic dynamic modulation driven by incoming audio. Input gain of up to 5x means it handles quiet signals and aggressive saturation alike. CV control over cutoff includes a front-panel accessible V/oct scaling trimmer, so it plays nicely with pitch sequences or melodic modulation.

One of Ikarie’s most powerful features is its stereo modulation architecture: use it to pan a mono signal between channels or to create filter detuning across the stereo field. Combined with modulation attenuverters and a flexible patch-programmable topology, Ikarie becomes a deep tool for sound sculpting, stereo animation, and spectral motion.

It’s a musical, tactile filter that encourages experimentation — and rewards it with spacious, expressive results.

Key Features

• Dual parallel state-variable filters (L/R), 12dB/oct slope

• Continuous lowpass–highpass mode control

• Voltage-controlled resonance

• Envelope follower with 3 decay time settings

• Up to 5x input gain — from subtle to saturated

• Stereo output VCA

• Beyond output for twin-peak spectral difference

• CV inputs with modulation attenuverter

• Stereo modulation: panning or filter detune

• V/oct input with front-accessible scaling trimmer

• Pingable filter cores for percussive or resonant applications

• Flexible internal routing via patching

• Width: 14HP

• Available in-store for demo