Jon Blackstone of Blackstone Appliances builds guitar distortion devices that generate low-order harmonics, and are responsive to dynamics. This is the type of distortion that re-shapes the body of the note, instead of coating it with a noisy fizz. As a guitarist/inventor, Jon has pursued these characteristics for many years, using a variety of technologies including overdriven tube output stages. Interestingly, he has achieved the best results not with tubes, but with small-signal MOSFETs and an unconventional input stage.