Modulation (Uni-Vibe / Rotary-speaker Chorus/Vibrato (expression pedal))
The Dunlop Rotovibe Chorus/Vibrato JD4S is an analog uni-Vibe / Rotary-speaker Chorus/Vibrato (expression pedal) pedal based on the photocell vibe / rotating-speaker emulation, with Depth (side-mounted knob), effect Speed (rocker treadle), Chorus/Vibrato mode selector; LED speed indicators controls, made in USA.
| Category | Modulation (Uni-Vibe / Rotary-speaker Chorus/Vibrato (expression pedal)) |
| Circuit / based on | photocell vibe / rotating-speaker emulation |
| Signal | Analog |
| Controls | Depth (side-mounted knob), effect Speed (rocker treadle), Chorus/Vibrato mode selector; LED speed indicators |
| Switches | Chorus/Vibrato mode switch |
| Footswitches | Effect on/off (bypass) |
| Bypass | buffered |
| I/O | 1/4" Input, 1/4" Output |
| Power | 9V DC |
| Power draw | 11 mA |
| Battery power | Yes |
| Enclosure | Treadle / rocker pedal housing |
| Country of manufacture | USA |
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