JAM Pedals RetroVibe Mk.4 Chorus & Vibrato Effect Pedal | No Limit Guitar Co, Idaho Falls
The JAM Pedals RetroVibe Mk.4 is a ground-up all-analog Uni-Vibe-style chorus and vibrato pedal widely regarded as one of the finest interpretations of the original effect ever built — available now at No Limit Guitar Co in Idaho Falls. Its lush pulse, vocal shimmer, and unmistakable warmth have earned it a devoted following among professional players including Paul Gilbert, Greg Koch, Joey Landreth, and Ruban Nielson of Unknown Mortal Orchestra. The Mk.4 builds on that legacy with a wider Depth and Speed range, plus new Tap Tempo and Ramping functions that invite deeper expressive control than any previous version.
Product Overview
The RetroVibe Mk.4 is built entirely on analog circuitry, preserving the organic, living quality that makes Uni-Vibe-style effects feel fundamentally different from their digital counterparts. The all-analog signal path produces the characteristic slow, liquid waves and fast, rotary-like spins that the original effect made famous, with a warmth and depth that respond dynamically to pick attack and playing dynamics. A toggle switch moves between Chorus and Vibrato modes, covering the full range of the effect's expressive territory.
Depth and Speed controls span a wider range than previous RetroVibe versions, with an LFO covering 0.5 Hz to 9.5 Hz for everything from imperceptibly slow sweeps to rapid, swirling rotary simulations. Tap Tempo is available via a dedicated TAP footswitch, allowing real-time speed synchronization on stage. A standard passive 10k expression pedal input provides continuous real-time control over modulation Speed, while an internal trimmer adjusts maximum output level to match the pedal's output to the rest of your signal chain.
The Ramping function is the Mk.4's most distinctive new addition: a prolonged press of the TAP footswitch engages a smooth transition from the current Speed setting to a second, user-selectable target speed. Ramp time — how long the transition takes — is set independently via the Depth knob while the TAP footswitch is held, enabling dramatic, controlled swells from slow throb to fast spin and back. This is a performance tool with no direct equivalent on competing Uni-Vibe pedals.
Ideal For
- Blues, rock, and psychedelic guitarists seeking the best all-analog Uni-Vibe chorus and vibrato pedal with professional-grade expressiveness
- Live performers who need Tap Tempo and Ramping for dynamic, real-time modulation control during performance
- Tone purists who demand true analog signal processing over digital Uni-Vibe emulation
- Expression pedal users wanting real-time Speed control over a high-quality chorus and vibrato effect
- Idaho Falls guitarists looking for a boutique-quality modulation pedal at No Limit Guitar Co
Key Features
All-Analog Uni-Vibe Circuit with Chorus and Vibrato Modes The RetroVibe Mk.4's fully analog design delivers the organic warmth, vocal shimmer, and lush pulse that define the original Uni-Vibe effect — qualities that all-digital implementations consistently struggle to replicate. Chorus mode produces shimmering, pitch-modulated width, while Vibrato mode shifts the pitch without the dry signal blend for a more dramatic, immersive effect.
Tap Tempo with Ramping Function The TAP footswitch allows real-time speed synchronization during live performance, and a prolonged press engages Ramping — a smooth, user-controlled transition between two independently set speeds. Ramp time is also user-selectable, giving players precise control over how quickly the pedal moves between slow and fast settings.
Wide Depth and Speed Range The Mk.4's LFO spans 0.5 Hz to 9.5 Hz, covering the full expressive range of the effect from barely perceptible movement to rapid rotary-style spin. The wider Depth control allows modulation sweeps from subtle shimmer to deep, dramatic pitch movement within the same pedal.
Expression Pedal Input A standard passive 10k expression pedal input provides continuous real-time control over modulation Speed, enabling fluid, hands-free transitions between slow and fast settings during performance — a particularly effective tool during extended solos or ambient passages.
True Bypass and Professional Build Quality True bypass switching removes the RetroVibe Mk.4 completely from the signal path when disengaged, preserving dry tone integrity. The pedal is built to JAM Pedals' boutique standard, with premium components throughout and a compact, pedalboard-friendly enclosure.
What's Included
- JAM Pedals RetroVibe Mk.4 Chorus + Vibrato Effect Pedal
- Manufacturer's warranty (contact No Limit Guitar Co in Idaho Falls for details)
- 9V DC adapter (tip-negative) sold separately; expression pedal sold separately
Technical Specifications
| Specification | Details |
|---|---|
| Pedal Type | All-analog Uni-Vibe-style chorus and vibrato |
| Modes | Chorus (C) / Vibrato (V) via toggle switch |
| Controls | Depth, Speed, TAP footswitch, Chorus/Vibrato toggle, internal output trimmer |
| LFO Range | 0.5 Hz – 9.5 Hz |
| Tap Tempo | Yes (TAP footswitch) |
| Ramping | Yes (prolonged TAP footswitch press; speed and ramp time user-selectable) |
| Expression Input | Yes (standard passive 10k expression pedal) |
| Bypass | True Bypass |
| Power | 9V DC adapter, tip-negative (sold separately) |
| Power Consumption | 120mA max |
| Input Impedance | 67kΩ |
| Output Impedance | <10kΩ |
| Dimensions | 4.7" x 3.9" x 1.9" (including jacks, pots, and footswitches) |
| Weight | 0.77 lbs. (350g) |
Get Your Hands on This Boutique Chorus & Vibrato Pedal Today
The JAM Pedals RetroVibe Mk.4 is a rare find — a boutique, all-analog Uni-Vibe pedal with the endorsement of some of the most tonally discerning players in the world. Stop by No Limit Guitar Co in Idaho Falls to plug in and experience the Ramping function and Chorus/Vibrato modes firsthand. Contact us or visit our website to check current availability before it moves on to the next pedalboard.
