BOSS GR-55GK-BK Guitar Synthesizer With GK-3 Pickup

The BOSS GR-55GK-BK is a guitar synthesizer and modeling floor processor supplied with the Roland GK-3 divided pickup. It gives guitarists a way to create synth, modeled guitar, bass, and conventional guitar sounds from one performance setup. The included GK-3 pickup captures each string separately for the GR-55’s polyphonic processing.

Designed for players who want sounds beyond a conventional pedalboard, the GR-55 can layer up to four sources: two PCM synth tones, one COSM modeled tone, and the normal guitar pickup signal. This lets a guitarist combine familiar guitar attack with piano, organ, string, pad, bass, or synth textures. It is suited to live performance, home recording, sound design, and MIDI-based music production workflows.

The sound engine combines two PCM tone generators with COSM guitar and amp modeling. Its PCM library contains 910 tone types, while modeling provides separate selections for guitar and bass modes. Editable patches, category-based sound access, and a graphic LCD help players move from ready-made sounds to more detailed programming.

The GR-55 provides dedicated processing for effects and amp-style tones, including multi-effects, preamp, modulation, delay, reverb, chorus, and EQ selections. Its 24-bit conversion and 44.1 kHz sampling support a detailed digital signal path for the GK pickup, normal pickup, and output stages. An onboard looper expands the unit’s use for practice and live layering.

For system integration, the GR-55 includes stereo outputs, a dedicated Guitar Out, headphones, MIDI input and output, USB computer connectivity, and a USB memory port. The computer USB connection supports MIDI and audio communication, while the USB memory port plays compatible WAV and AIFF files with foot control. The included GK-3 pickup and 5 m GK cable provide the key connection between a compatible electric guitar and the processor.

Key Features

• Four-Source Layering: Combine two PCM tones, modeled tone, and normal guitar signal.
• GK-3 Pickup Included: Provides divided-string sensing for compatible electric guitar installation.
• 910 PCM Tone Types: Access pianos, organs, strings, synths, and more.
• COSM Modeling: Create modeled guitar, bass, synth, and amp sounds.
• USB Audio and MIDI: Connect to a computer for audio and MIDI.
• Foot-Controlled USB Playback: Play WAV or AIFF files from USB memory.

Design & Installation

The GR-55 uses a floor-oriented design with an integrated expression pedal, foot controls, a 240 x 64-dot graphic LCD, and rear-panel connection points for guitar, audio, MIDI, USB, and power. Roland does not publish a chassis-material specification, but the layout is designed to keep patch selection, expression control, and performance functions within foot reach. The unit measures 405 mm wide by 244 mm deep and has a maximum height of 106 mm when the expression pedal is moved to its minimum position.

Install the included GK-3 divided pickup on a compatible steel-string electric guitar, then connect it to the GR-55 GK IN using the included 5 m GK cable. A conventional guitar pickup alone cannot directly provide the separate-string signals required for GR-55 synth and modeling operation. Connect the OUTPUT L/MONO and R jacks to a full-range amplification or recording system, use GUITAR OUT when routing the dry guitar signal separately, and connect USB to a computer or supported USB flash memory as needed.