ADCOM GFA-555 MK2 boards are here! Posted on August 6, 2019 by hoppesbrain Hi everyone,My GFA-555 MK2 boards are ready to go! Thanks to Jon Morris of Morris Audio in Wyoming for helping me work out the bugs and validate the design. He’s already restored a few customer’s GFA-555 MK2’s with my boards. Get one here in my store. – GFA-555 MK2 Input Board NEW – I am now offering these boards fully assembled and tested for $380. All you need to do is make sure your power supply and output section are good.