The old Ibanez DM2000 rack delay unit does a cool trick; when you turn the modulation speed to the minimum and the depth/width to the maximum. then get a note repeating infinitely using the hold feature, turning the modulation on will cause the repeat to slowly rise up in pitch about an octave as it speeds up and then down an octave lower as it slows down. It will cycle like this with the pitch rising and falling as long as the hold feature and Mod are on. Phish fans will probably know this sound.
The Raster 2 can get pretty close to this sound. While the Raster 2 doesn't have a "hold" per se, it does have infinite repeats. Some adjustment of the feedback may be necessary to "tune" it to your instrument's tone and volume characteristics in order to get the repeats to go on and on without distorting.
Here's the recommended settings to get it in the ballpark:
- SHIFT: 12:00
- FDBK: 3:00
- DELAY: 12:200
- BLEND: 12:00
- RATE: 9:00
- DEPTH: 5:00
- TONE: 12:00
- All other ALT knob settings can be at 12:00
- Shift mode: Transpose
- Feedback Mode: Forward / Shift Once
- WAVE: Triangle or Sine
- Left footswitch: Shift Latching
- Mod Dest: Shift
- Right footswitch: Momentary
We recommend to set the Raster's ON footswitch to Momentary contact so it only records when the switch is held down. When you want to hear the rising and falling, you can engage the SHIFT switch, or adjust the modulation DEPTH starting from 0 to full to avoid a sudden jump in pitch.