13-Pin Input Breakout

Roland/BOSS GK guitar interface for hexaphonic or polyphonic processing


The 13-Pin Input Breakout module receives signals from a Roland GK-3 compatible guitar and converts them to modular levels using low-noise audio op-amps.

Gain options include 10x (20dB), 30x (30dB), or 100x (40dB).

Gain controls allow you to adjust the gain from zero to full-scale in the amplified string outputs.

Amplifier boards are easily replaceable with different gain versions.  Check the shop for replacement boards.

The module provides power to the electronics in your GK-3 compatible guitar.

Hand-built in the USA.

Important Note:

This module has been tested successfully with Roland GK-3, GK-2A, Graph Tech Hexpander, and RMC Poly-Drive pickup systems.

Roland GK-2A pickups (including those on the Fender GC-1) require a special version of this module.


Please indicate if you intend to use a Roland-ready or GC-1 Stratocaster with this module at the time of your order and we will supply the special version.


  • Outputs for each signal in the 13-pin GK-3 interface (audio/CV).

  • Access to direct signals from each string and the passive pickup.

  • Selectable gain range (1x or 10x, 30x, 100x) for each string and the passive pickup output on back of the module.

  • Adjustable gain or attenuation to zero within each selected gain range.

  • Metal film resistors for close channel gain matching.

  • Pairs well with 13-Pin Output Breakout , Hex VU Meter, Hex Fuzz, Hex VCF, Hex VCA, and Hex EF-Gate-Trigger.

  • Ideal for guitar multi-channel, single-string, or hexaphonic effects processing.

Technical Specifications:

Width     16 HP                           

Depth     40 mm                                       

Power     39 mA @ +12V

                 39 mA @  -12V

                   0 mA @  +5V

Gain        0-20 dB, 0-30 dB or 0-40 dB optional

Reverse power protection, resettable fuses, extensive power supply filtering

View the Manual

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