The API TranZformer GT guitar pedal and DI box uses the company's renowned discrete circuitry and transformer-coupled output to bring the iconic API tone onto your pedalboard. It all starts with a high-headroom input stage hitting a variable compressor based on the feedback mode of the 525 module with six different compression settings. Next down the line is the tone control section, a take on the 553 program equalizer with three bands and center frequencies carefully selected for getting the punchiest guitar sounds.