They both hiss enough to hear… (more than a normal pedal should) The trick is to put a buffer before them. that will reduce the hiss almost entirely. I have both pedals on my board so I know this works. The pedals are great! which makes up for a little hiss. You can almost eliminate it with a buffer. This is the best buffer out there! http://www.wamplerpedals.com/buffer The company is great! and they make high end products. I have several of their pedals on my board.. the HotWired OD and the Ego Comp are my favorite.