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The built-in echo has a vintage tone and its repeats are ever-so-slightly spread in the stereo field to widen up patches.
On switch- Guess what? This turns on the Echo effect.
Time- Sets delay time, from 1 to 2000 ms. If the Sync button is enabled, time settings snap to synchronized note values.
Sync- The Sync switch locks the delay time to master tempo. When engaged, the Time knob snaps to note values ranging from 1/64th note triplet to 8 beats. Sync mode locks to the tempo in the top toolbar when using the SEM standalone version or the current project tempo when the plug-in version is used in a DAW.
Feedback- Routes the output to the input for additional repeats. Be careful at high settings as this can result in runaway feedback madness.
Mix- Sets the ratio of clean to effected sound.
Phasor
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This one is admittedly ridiculously simple, but its DSP was created by our frequent collaborator, Mark Barton (MRB). He managed to dig up the circuit diagrams for the rare-as-hen's-teeth Oberheim Phasor stomp box and modeled it, and it sounds awesome.
On switch- Turns on the Phasor effect.
Speed- Sets the phaser's internal LFO speed from 0.10 to 5 Hz. The LED flashes at the current mod rate.