Walrus Audio Fathom Multi function-reverbThe Fathom is a feature rich reverb with 4 different customized reverb algorithms to choose from. Easily go from tasteful, small room reverb to long, modulated trails dripping of ambient goodness. The toggle switch adds options for low, medium and high modulation. Use the dampen knob to fine tune the tone of the reverb's decay. The Fathom features 4 different algorithms. Hall Wide, open and vast with decay that ends with high frequency rolloff. X knob