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BOSS GM-800 Guitar Synthesizer Effects Pedal w/ GKC-AD 13-Pin GK Converter


BOSS GM-800 Guitar Synthesizer Effects Pedal w/ GKC-AD 13-Pin GK Converter


Manufacturer's Description

BOSS GM-800 Guitar Synthesizer Effects Pedal

BOSS Guitar Synthesis Evolves with the Power of ZEN-Core

The GM-800 elevates guitar synthesis into a new age of natural playability and boundless creative range. Driven by the newly developed Serial GK interface, the advanced ZEN-Core engine unlocks any sound imaginable—from acoustic instruments to classic and modern synths—while high-performance DSP delivers tracking stability and expressive scope never before possible. Freely combine and edit Tones with the intuitive Scene workflow, color sounds with a huge selection of effects, and explore a universe of fresh content on Roland Cloud. Compact, streamlined, and ultra-versatile, the GM-800 infuses your guitar or bass with unlimited musical potential.


BOSS and its parent company Roland have been the worldwide leaders in guitar synthesizer innovation for nearly five decades, beginning with the revolutionary GR-500 system in 1977. The GM-800 continues our dedication to this category, providing guitar and bass players with powerful creative tools and access to sounds typically only available with keyboard-based instruments. Expanding and elevating the concepts behind many historic Roland GR products, the GM-800 merges our latest pitch and string tracking advancements with a versatile, cutting-edge sound engine.


The GM-800 is built around the expandable ZEN-Core Synthesis System, the sound source behind professional Roland products like the JUPITER-X and FANTOM keyboards, the ZENOLOGY software synthesizer, and many others. ZEN-Core is the most powerful synth engine in Roland’s long history, distilling decades of expertise into one sonically vast and deeply expressive creative instrument.

Over 1200 Sounds at Your Fingertips

The ZEN-Core engine combines modern PCM synthesis and advanced modeling to bring you an infinite playground for sonic discovery. Play acoustic pianos, EPs, organs, and orchestral instruments. Tap into classic Roland synths like the JUPITER-8, JUNO-106, and many others. And combine them all together to build sounds never heard before.

Four Tones Plus Rhythm

The GM-800 features four Tone parts plus a Rhythm part filled with acoustic and electronic percussion sounds. Call up a part with the dedicated panel buttons, then explore a deep array of synth parameters, pitch settings, alternate tunings, and string assignments to shape sounds to perfection.

Intuitive Scene Workflow

The ZEN-Core workflow is based around Scenes, which are “super patches” containing every element in a sound: Tone selection, parameters tweaks, sensitivity and other play settings, effects, and more. And thanks to the muscular DSP, you can carry over the sound of the current Scene as you select a new one for seamless musical transitions. There are 150 user-configurable Scenes, and 100 come with pro sounds ready to play immediately.

Roland Cloud Expansion

The GM-800 supports an ever-growing range of creative options through Roland Cloud. Stay inspired with ZEN-Core Sound Packs and Wave Expansions. And play the ZENOLOGY synthesizer and legendary Roland instruments in your DAW from your guitar or bass. You can start using Roland Cloud right away with a free Roland Account and access additional content via three paid membership levels. All plans start with a free 30-day Ultimate trial to experience everything Roland Cloud has to offer.


The GM-800 packs the full effects range of the modern ZEN-Core system. With an immense variety of effect types available in each Scene, you can shape, enhance, and mangle sounds to your heart’s delight.

Dedicated MFX for Each Part

Along with their sound-shaping parameters, every Tone and Rhythm part has a dedicated MFX processor. Each offers over 90 effect types, including distortions, filters, mod effects, delays, and more. Many selections include two effect types for additional sound-shaping control.

Scene and System Effects

Within every Scene, you also get two additional FX for processing the combined sound, plus high-quality chorus/delay and reverb effects with independent send levels from each part. And with the Master Comp and EQ, you can shape the GM-800’s sound output for any recording or performance setup.


The GM-800 lets you harness an endless variety of sonic textures using the expressive playing characteristics of your guitar and bass. Optimize the performance with continuous pitch control or chromatic operation. Layer Tones to create rich, combined voices. Or assign them to individual strings, such as a bass sound on the low strings and a piano or sax sound on the high strings. You can even assign Tones to specific fret ranges, a powerful new feature made possible with the GM-800’s advanced pitch detection.


The GM-800 delivers accuracy, stability, and real-time playability standards that far exceed previous systems, realized through skilled BOSS engineering and a high-speed processor dedicated solely to tracking. Multiple velocity and feel parameters let you dial in the optimal response for every sound and style. For example, you can set a Scene with piano sounds to respond to every dynamic nuance—from soft to loud—while setting another Scene with vintage analog synth sounds to the fixed velocity response found in the original instruments.


The streamlined GM-800 flows smoothly from desktop operation to installation on an advanced pedalboard. The four footswitches default to Scene selection and two unique control settings, such as pedal hold, pitch bend, or Tone selection. But you can freely assign them to control a variety of functions via a powerful Assign matrix. Two external control jacks are also available, each supporting up to two footswitches or an expression pedal. And with five-pin MIDI I/O, you can interface with MIDI equipment from vintage to modern.


Along with standalone operation, the GM-800 merges seamlessly into a variety of expanded creative environments.

Edit Sounds with BOSS Tone Studio

Craft Scenes in detail from your computer using the BOSS Tone Studio software for the GM-800. Set up Tones, string assignments, sensitivity, and more from a large, friendly interface. Then use the Librarian function to organize your Scenes for different songs and performances.

Audio/MIDI Interface

With a single USB cable, you can capture GM-800 sounds as audio tracks in a DAW and “re-synth” sounds in a similar way to the re-amp technique used with standard guitar tones. A Guitar to MIDI function is also available, allowing you to play virtual instruments over USB and trigger hardware sound modules via the MIDI output.

MIDI Sound Module

The versatile GM-800 can do double duty as a compact, go-everywhere MIDI sound module. Connect a keyboard or other MIDI controller to the five-pin MIDI input to play sounds live. Or use the ZEN-Core engine as a premium USB sound source within your music production workflow.

Multifaceted Connectivity

The GM-800 features the newly developed Serial GK digital interface, which supports guitar/bass input from a BOSS GK-5 or GK-5B Divided Pickup and easy linking of multiple GM-800 units. GKC-AD and GKC-DA conversion boxes are also available for classic 13-pin GK devices, allowing you to drive the GM-800 with a Roland GK-3 or GK-3B pickup and use Serial GK devices with the BOSS SY-1000 and GP-10.


  • Next-generation guitar and bass synthesizer with the newly developed Serial GK interface
  • Advanced ZEN-Core sound engine derived from flagship Roland synthesizers
  • Natural playing feel and solid tracking stability, realized through high-performance DSP
  • Powerful Scene workflow with four Tones plus Rhythm
  • Vast onboard sound library with over 1200 Tones and 70 Rhythm sounds
  • Explore Sound Packs, Wave Expansions, legendary Roland instruments, and more on Roland Cloud
  • Deep editing tools for each Tone, including sound parameters, sensitivity settings, and more
  • 150 user-configurable Scenes, including 100 Scenes with professional ready-to-play sounds
  • Over 90 total effect types available in each Scene
  • Space-saving design flows into every setup, from pedalboard to desktop
  • Serial GK expansion jack for connecting to another BOSS guitar synthesizer product
  • Two external control jacks, each with support for up to two footswitches or an expression pedal
  • USB audio/MIDI connectivity and standard MIDI I/O
  • Guitar to MIDI function for playing external MIDI instruments via USB or a MIDI cable
  • Also functions as a standalone synthesizer sound module for MIDI keyboard use or DAW sound expansion
  • Edit Scenes and organize sounds on your computer with BOSS Tone Studio
  • Download and share GM-800 Livesets at BOSS Tone Exchange*

BOSS GKC-AD 13-Pin GK Converter for GM-800 Guitar Synthesizer & GK-3 / GK-3B-Equipped Instruments

The latest BOSS guitar synthesizer products feature the Serial GK digital interface, a newly developed connection method that delivers evolved performance over the analog 13-pin GK interface used in earlier BOSS and Roland guitar synth and modeling products. The GKC-AD GK Converter allows you to drive the Serial GK input on the GM-800 Guitar Synthesizer from a Roland GK-3 or GK-3B Divided Pickup or an instrument equipped with a 13-pin GK output.


  • Converts analog 13-pin GK pickup systems to the newly developed Serial GK digital interface
  • 13-pin GK input and Serial GK output
  • Instrument output for passing normal guitar/bass pickup sounds embedded in the 13-pin connection
  • Compact and rugged metal design


BOSS GM-800 Guitar Synthesizer Effects Pedal


  • Sound Generator: ZEN-Core
  • Parts: 5 parts (Play part: 4, Rhythm part: 1)
  • Tones
    • Preset tone: 1,200 or greater
    • Preset Drum Kit: 70 or greater
    • Import tone: 256
  • Scenes: 150
  • Effects
    • Part Multi-Effects: 1 system (for each part), 93 types
    • Part EQ: 1 system (for each part)
    • Reverb: 7 types
    • Chorus/Delay: 9 types
    • Scene MFX: 2 systems (Serial or Parallel selectable), 93 types
    • Master EQ / Comp
  • Nominal Output Level: OUTPUT (L/PHONES, R/MONO): -10 dBu
  • Maximum Output Level: OUTPUT (L/PHONES, R/MONO): +7 dBu
  • Output Impedance: OUTPUT (L/PHONES, R/MONO): 44 ohms
  • Recommended Load Impedance: OUTPUT (L/PHONES, R/MONO): 10 k ohms or greater (Phones: 44 ohms or greater)
  • Controls
    • SCENE DOWN switch, SCENE UP switch, CTL1--2 switches
    • PART1--4 buttons, PART R button, EXIT button, WRITE button, MENU button, PAGE buttons
    • 1--4 knobs, SELECT knob, OUTPUT LEVEL knob
  • Display: Graphic LCD 256 x 80 dots
  • Connectors
    • GK IN jack: 1/4-inch TRS phone type (for BGK cable only)
    • GK OUT jack: 1/4-inch TRS phone type (for BGK cable only)
    • OUTPUT (L/PHONES) jacks: 1/4-inch TRS phone type
    • OUTPUT (R/MONO) jacks: 1/4-inch phone type
    • CTL3, 4/EXP1 jack, CTL5, 6/EXP2 jack: 1/4-inch TRS phone type
    • USB COMPUTER port: USB B type (supports High-Speed USB, USB Audio, and USB MIDI)
    • USB MEMORY port
    • MIDI connectors (IN, OUT)
    • DC IN jack
  • External Memory: USB Flash drive (sold separately)
  • Power Supply: AC adaptor
  • Current Draw: 840 mA
  • Accessories
    • AC adaptor (PSB-1U + AC Cord Set)
    • Quick Start
    • Rubber foot x 4
  • Options (sold separately)
    • Divided pickup: GK-5 (for guitar), GK-5B (for bass guitar)
    • Serial GK cable: BGK-15 (15 ft./4.5 m), BGK-30 (30 ft./9 m)
    • GK converter: GKC-DA, GKC-AD
    • Footswitch: FS-5U, FS-5L, FS-6, FS-7
    • Expression Pedal: EV-30, FV-500L, FV-500H, Roland EV-5
    • AC adaptor (PSB-1U) (*1)
    • *1 When purchasing an AC adaptor, be sure to specify the adaptor (from the list that follows) that is designed
    • for the region in which it will be used, and the voltage supplied there.

Size and Weight

  • Width
    • 246 mm
    • 9-11/16 inches
  • Depth
    • 134 mm
    • 5-9/32 inches
  • Height
    • 63 mm
    • 2-31/64 inches
  • Height (including rubber foot)
    • 65 mm
    • 2-9/16 inches
  • Weight (excluding AC adaptor)
    • 1.2 kg
    • 2 lbs 9 oz

BOSS GKC-AD 13-Pin GK Converter for GM-800 Guitar Synthesizer & GK-3 / GK-3B-Equipped Instruments

  • Connectors
    • GK IN connector: 13 pins DIN type
    • GK OUT jack: 1/4-inch TRS phone type (for BGK cable only)
    • GUITAR OUT jack: 1/4-inch phone type
    • DC IN jack
    • USB port: USB Micro-B (program update only)
  • Nominal Output Level: GUITAR OUT: -10 dBu
  • Recommended Load Impedance: GUITAR OUT: 10 k ohms or greater
  • Indicators: GUITAR IN: 1 M ohm
  • Indicators
    • POWER indicator
    • GK CONNECT indicator
  • Current Draw: 240 mA
  • Power Supply: AC adaptor
  • Accessories
    • AC adaptor
    • Owner’s Manual
  • Options (sold separately): Serial GK cable: BGK-15 (15 ft./4.5 m), BGK-30 (30 ft./9 m)

Size and Weight

  • Width
    • 115 mm
    • 4-17/32 inches
  • Depth
    • 92 mm
    • 3-5/8 inches
  • Height
    • 36 mm
    • 1-7/16 inches
  • Weight
    • 340 g
    • 12 oz