Amp Modeling Algorithm for easy Tone Tweaking The White-box Amp Modeling & Pre-Efx algorithm offers realistic playability and analog-chaos response. The concept of "Chaos makes the muse" perfectly applies to the analogue circuit. When you tweak the knob, it affects itself as well as other parameters. For a linear digital system, the parameter is independent. The white-box algorithm offers real-time feedback, increment-by-increment. NUX TS/AC-HD replicates the same playability most guitarists crave in a real tube amplifier. 2 Powerful DSP Chips for High-Definition MG-400 houses 2 powerful DSP chips for high-definition White-Box Amp Modeling algorithm (TS/AC-HD) and Core-Image post-effects. MG-400 sets moveable signal blocks, 12 IR COLLECTION slots, flexible P.L block with MIN & MAX parameter setup, abundant SYSTEM MENU, and physical MASTER volume knob.