The Roland E-4 Voice Tweaker is a portable vocal effects processor and looper from the AIRA Compact series. It harmonizes, auto-tunes, vocodes, loops, and glitches your voice through a hands-on interface designed for real-time performance. A 1/4" mic input, pitch and formant sliders, and a 24-second looper with overdubbing give vocalists, beatboxers, streamers, and sound designers a deep toolkit in a pocket-sized format.

Vocal Processing & Looper

The E-4 combines studio-grade vocal processing with a performance-oriented layout. Dedicated Pitch and Formant sliders let you shift your voice up or down a full octave and reshape its character in real time, moving between deep bass, natural, and chipmunk territory with smooth, artifact-free transitions. Auto Pitch provides hard-tuned vocal correction, Harmony generates multi-part vocal arrangements, and a full Vocoder with variable waveforms (sawtooth, square, pulse, noise) creates classic robotic textures.

The Scatter knob introduces rhythmic glitch effects synced to tempo, chopping and rearranging audio in unpredictable patterns. A 24-second looper with unlimited overdubbing, undo/redo, and automatic BPM detection lets you build layered vocal performances on the fly. All of this connects to other AIRA Compact units via sync I/O and AIRA Link for synchronized jams.

Specifications

• Effect Types: Auto Pitch, Harmony, Vocoder, Pitch, Formant, Scatter, Reverb, Delay, Echo, Chorus
• Looper: 24 seconds with unlimited overdubbing, undo/redo, auto BPM detection
• Low-Cut Filter and Noise Gate: Built-in
• Inputs: 1/4" mic input (wide-range gain), 1/8" mix in / headset (CTIA compatible)
• Outputs: 1/8" mix out / headset
• MIDI I/O: 2x 3.5mm TRS (in/out)
• Sync I/O: 2x 3.5mm (in/out)
• USB: Type-C (class-compliant audio/MIDI, no drivers required)
• Display: 4-character LED
• Power: Rechargeable lithium-ion battery or USB bus power (500 mA)
• Battery Life: Approx. 3.5 hours (charges in approx. 3 hours)
• Dimensions: 188 x 106.5 x 41.7 mm (7-7/16" x 4-1/4" x 1-11/16")
• Weight: 290 g / 11 oz

In the Box

• Roland E-4 Voice Tweaker
• "Read Me First" leaflet
• USB Type-C to USB Type-A cable