ASTR is a stereo shimmer reverb built around a four-line feedback tank with a pitch shifter inside the loop. Every trip around the tank climbs another octave, so a chord blooms upward into a high, glassy tail — and with SHIM at zero, the same tank is a plain, dark hall.

DECAY sets the tail length, from 0.3 seconds to roughly 25 seconds; the loop gain is capped below unity, so the reverb blooms but never self-oscillates. SIZE stretches all four tank lines from 0.7x to 1.6x, TONE damps the recirculating signal from dark and close to bright and open, and MIX blends dry and wet. Every knob has its own CV input, and the right input normals to the left for mono sources.

• Stereo in / stereo out; right input normalled to the left
• +12 semitone pitch shifter inside the feedback path — each recirculation climbs an octave
• DECAY: RT60 from 0.3 s to about 25 s, loop gain capped below unity (blooms, never self-oscillates)
• SIZE: room scale — stretches all four tank lines from 0.7x to 1.6x
• TONE: damping inside the tank, dark and close to bright and open
• CV inputs for DECAY, SHIM, SIZE, TONE and MIX