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Featuring ten combo options, four speaker cabinet emulations and a three-band EQ with additional presence control, the Boss GP-20 Amp Factory gives you hundreds of tonal configurations all in a dual-stomp design. Capable of going from classic tweed to British muscle with a few turns of a knob, the GP-20 gives you a room full of cabs and combos without crushing your wallet.

Product Specs

  • GP-20 Amp Factory
  • Black
  • 2000s
Made In
  • Taiwan

From the Price Guide

Reviews for the Boss GP-20 Amp Factory
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  • Great Dual Pedal Effect

    Verified Purchase

    If your into amp modeling (which I find best for recording) this is a great addition to any hardware amp modeler collection you may own. I have three Line 6 hardware modelers (AM4, PODxt Pro, POD HD Pro) among some other stompbox amp modelers, so am intimately familiar with them. If you want to use…

  • The Boss GP-20 Amp Factory

    Verified Purchase

    I use small tube amps, the Blackheart Little Giant BH5-112 (re-tubed for more crunch) , or a Kustom Defender 5H with matching speaker cabinet. The Boss GP-20 Amp Factory adds all the oomph I need. Many cool sounds from a small portable box, and I got a great deal on REVERB!! I have no regrets!! I would recommend it to anyone on a budget or looking for a new sound.

  • Good emergency tool (or fun toy)

    Verified Purchase

    I generally play guitar through a clean Fender combo or an acoustic combo or straight to PA system. I don't own any specialty high gain amps. This pedal lets me play with those sounds on the cheap and they don't sound too bad. Also a great emergency tool small enough to keep in the gig bag in cas…