Hands down, one of the best envelope filters out there. The Q-Tron opens up endless expression and experimentation with it's cool voice and sensitive controls. Need to add flavor to those Bootsie-esque slaps or some punch to those Garcia solo excursions? If so, this box has the tools for both funking and jamming. The Q-Tron is ultra-responsive and you'll need to adjust your playing if you've been playing through lo-budget DOD and Boss models. After some adjustments in your playing the Q-Tron comes alive and that responsiveness makes for some very nice interaction between your guitar and the effect. It's a very seemless and fluid unit and comes very close to the much applauded Mutron III in terms of sound and delivery. Even though we had this thing squawking and talking right out of the box, the manual is worth reading for a clearer understanding of this classic effect.