Long Delay

A free-running stereo echo built for long delay times — up to four seconds — and the dub, ambient, and slow-wash territory that needs them. The two channels run as independent delay lines, so each side echoes only itself and the stereo image of whatever you feed in is preserved.

How it works

The delay length is one-pole smoothed, so turning Time doesn't click — it glides between settings, dragging the repeats with it for tape-style pitch slurs. The tap itself is read with Hermite interpolation for clean, artifact-free echoes even mid-sweep. Feedback tops out below unity, so repeats decay rather than run away, and Tone sits inside that loop as a damping filter — left open the echoes are bit-identical copies, but pulled back they lose brightness with every pass for a proper dub-style fade.

Controls

• Time — echo time, sweeping exponentially from 0.1 s to 4 s. Short for slapback and tight rhythmic echoes, long for cavernous dub tails.
• Fbk — feedback: how many times each echo regenerates. Higher means longer trails; it's capped so it won't self-oscillate into a runaway howl.
• Mix — how loud the echoes sit on top of your dry signal. The dry stays at full level throughout; turn this down to pull the repeats back, up for the loudest tails.
• Tone — feedback damping: how bright each repeat stays as it decays. At 100% the loop runs fully open and the echoes keep their full-band detail, identical on every pass; turn it down and a low-pass (bottoming out near 1 kHz) shaves the highs off the wet tap before it re-enters the loop, so each successive echo grows darker and more diffuse — the classic tape/dub fade.

Inputs & outputs

• In L / In R — the stereo signal to echo; each side is delayed on its own, so width is kept intact. Patch one side for a mono source.
• Time / Fbk / Mix / Tone CV — voltage control over each knob; patch an LFO or envelope to any of them. Modulate Time for warbling, pitch-bending tape effects, or sweep Tone to open and close the trails over time.
• Out L / Out R — the stereo wet-plus-dry result.

Tips

• Sweep Time by hand or with slow CV while feedback is high to smear the trails into pitch-shifting waves.
• High Fbk with a long Time turns a few notes into an evolving ambient bed — feed it back into a filter or reverb for endless washes.
• Roll Tone back when feedback is high so each repeat fades darker than the last — it keeps long, dense trails from building up harsh highs and gives them that warm, tape-echo decay.