Echo is RC-20’s feedback delay, with RC-20 inside the loop (see How the Echo works). If a preset doesn’t use it, switching it on gives you a starting point: Big Knob at 20%, Feedback at 30% and Cut from 80 Hz to 5 kHz.
- Big Knob Blends your sound with the echoes: equal at 50%, echoes only at 100%. It sets how loud the echoes are, while the Echo amount sliders set how much each module colors them.
- Echo amount sliders The thin slider under each of the Wobble, Distort, Digital, Space and Loss Big Knobs sets how much that module processes the echoes. The module must be switched on. Hold [Cmd] (Mac) / [Alt] (Windows) to move all five together.
- Enable, Solo and The button at the top left switches the Echo on and off. Hover over the Echo to reveal S (Solo), which plays only the echoes.
- Lock Hover over the Echo to reveal the padlock, which keeps your Echo settings (minus the sliders) when you change presets.
- Feedback How many repeats you get. Above 100%, the knob shows a red zone and the echoes build up instead of fading, while a limiter keeps them from running away completely.
- Clear The small button on the Feedback knob empties the Echo. Hold it to keep it empty until you let go.
- Left and Right Drag the thin sliders above (Left) and below (Right) the time display to set the time between repeats. With sync on (the default), pick a note value from 1/32 to 2 bars. With sync off, set any time from 2 ms to 8 seconds. Each side has its own sync button. If a time can’t be played, its Help Tip shows a warning, for example when Loss in Codec mode sets a minimum echo time.
- Link With Link on (the default), Right follows Left, sync included. Switch it off to set them separately.
- Scrub Drag it to bend both echo times up or down, like scrubbing a tape loop by hand. It springs back when you let go, so the pitch swoops and settles.
- Width At 0% the echoes are mono, and at 100% they keep their stereo image. Higher settings, up to 200%, spread them wider.
- Ping/Pong Bounces the repeats between left and right, starting on the side you turn it to.
- Duck Pushes the echoes down while your sound plays, so they come up in the gaps.
- Smooth Softens the attacks of the repeats, a little more on every pass.
- Cut A low and high cut inside the loop, so the echoes get thinner and darker as they fade.
- Flux Makes the echo times drift randomly, like tape.
- Grains Turns the echoes into a cloud of tiny snippets. The Grains knob mixes them in, in place of the normal echo. Pitch transposes them by up to 24 semitones either way (hold [Shift] for values in between). Reverse plays them backwards. Invert plays some of them at the opposite pitch, so +12 becomes −12.