The CASCADE DELAY is a dual PT2399 design. This module consist of 2 PT2399 chips, Delay A and Delay B. Each delay section consist of its own parameters - Delay time, feedback and feedback into the opposing delay’s input allowing each delay to feedback into each other.
CV control over delay time is also onboard with a selectable switch to control the delay time over both delays or just delay B, leaving delay A set to its knob setting.
PT2399 IC's can be found HERE
No calibration is required for this module.