ScratchLoopDelay
Mix = WET: 50
Pitch Mix = A10+B10
Pitch A = A: UNISON
Pitch B = B: UNISON
Delay A = A: 1/8
Delay B = B: 1/16
(encoder) = DIATONIC / TMP: ON
Depth / Key = (any) N/A
Speed / Scale = (any) N/A
Xnob = FB-A: 75
Ynob = FB-B: 75
(EXP PED Heel) = B: 1/16
(EXP PED Toe) = B: 1/2
Controls level of Voice A (Voice B) feedback. The feedback delay length is Delay A or Delay B, whichever is longer.
The excerpt above (from the Diatonic section of the UM) explains the idea behind this preset. In the default settings, this is just a rapid ping-pong delay with a somewhat long decay time. But when you start to vary the delay times …
Expression Pedal:
By controlling the delay time in Delay B, the expression pedal shifts the feedback delay length between the 1/8 note static setting in Delay A, or the current expression pedal setting (if it's longer than an 1/8th note) in Delay B. Active use of the EXP PED yields scratching & stuttering delay effects. The feedback length remains sync'ed to tempo, but the changing divisions result in a very unique delay effect.
