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Tunnels effect

Feedback Rack

Feedback Rack is a tunnel and feedback effect in FRCTL, the browser VJ studio. A rack of feedback types. Every slider is a different kind of feedback and zero switches it off, so they stack: swell with spin is a spiral, rise with melt is smoke.

Runs live on video, images, a camera or generated art. Stack it with any other effect, and route LFOs, envelopes or any of ten audio bands to its controls so it moves with the music.

Try Feedback Rack free All effects

The untouched demo art: an eye inside a triangle over wavy teal, blue and peach lines — Source

The eye-in-triangle in peach and teal, its lines smeared outward into rippled trails with faint rainbow fringes — Feedback Rack, default settings

What Feedback Rack does

Seven kinds of feedback on seven sliders, each off at hard left, composed into one read so they stack. Trails only survive where they outshine the live picture, so the source stays crisp. At default Swell and Spin stream edges out in a spiral and Prism fans them into rainbow rings, while Rise adds smoke, Melt makes trails ooze and Mirror folds them six ways.

Using Feedback Rack

Where it works: Live performance, since each slider is a different trail you can fade in on a fader, and it's the fastest route to smoke or kaleidoscope trails on a logo. Keep it last in the stack.
With the music: It doesn't hear the music. MIDI-map the sliders to faders and ride them, send B1 (kick) to Echo so kicks leave ghosts, and let a bar-synced LFO on Mirror fade the kaleidoscope in and out.
Starting point: Swell centre, Spin a quarter, Prism a quarter, everything else hard left, then bring up Rise or Melt one at a time.

Controls

Echo: Plain trails. The last frame straight back in, so anything that moves leaves a ghost behind it.
Swell: Each pass grows out of the centre, so the picture streams towards you like a tunnel run in reverse.
Spin: Each pass turns about the centre. On its own it is a vortex; with swell it becomes a spiral.
Rise: Each pass lifts and sways, so bright edges climb the frame like smoke.
Melt: Each pass is pushed through a slow flow field, so trails pool and ooze instead of travelling in straight lines.
Mirror: Each pass is folded six ways round the centre, so trails come back as a kaleidoscope.
Prism: Each pass splits red outward and blue inward, so trails fan into rainbow rings.
Speed: Rate of the effect motion. Centre is the authored speed, hard left a tenth of it.

Pairs well with Feedback Rack