All crossbows are noisy, but one that I've shot is surprisingly quiet- the Barnett RC-150. It's very small, maybe that's why it is quieter, but I would say it is only slightly louder than my PSE compound bow, and much, much quieter than my Horton X-bow. Of course, it is shooting a short arrow at a fairly low velocity, so it's only good for close range shots anyways.