ACL VC Dual Delay

The recently popular Princeton delay chip PT2399 is the heart of this delay as well yet this module houses two individual delay units with their own, open feedback loops, low- and high frequency cut in the feedback and voltae control of delay time. Things get interesting by normalizations of delay A to B and the simple and intuitive routing of the delays and feedbacks.

The delay time is set with the Rate potentiometer and with a control voltage. The modulation input IN CV has a bi-polar attenuator (Rate CV). The sensitivity of the modulation input can be multiplied by ten with the NORM / x10 switch.

Feedback: in the, usually closed, feedback loop of each delay two filters are integrated for dampening the highs and lows of the echo. These LO CUT and HI CUT filters a have a slope of 6dB and do not feature voltage control.

The feedback path can be opened whend desired, for that task two outputs and one input are available: FLT FB OUT emits the filtered feedback signal while FB OUT carries the non-filtered signal. The feedback signal can now be processed and injected back to the delay via the FB IN socket. The feedback amount and polarity are set with the according bi-polar attenuator i.e. positive and negative feedbacks are possible.

Routing of the delays and feedback paths is altered in the ROUTE section. The delays can be routed either in parallel (as two totally independent delays) or in series. The feedback paths are routed either in usual parallel fashion or crosswise, which in combination with the positive / negative feedbacks can lead to really interesting results like strange modulated reverberated space. The audio inputs and CV inputs of A unit are normalized to the B unit.

Because the module is not intended to be a usual delay but more an experimental tool, e.g. for adding a short reverb tail to sounds, there is no dry/wet control. The OUT socket always emits 100% wet material.