Is there an object that can cut off any signal below or above a certain amplitude?

[expr~ if($v1 < $f2, 0, $v1)]

The cutoff time will be instant, but it should work.

Made a simple gate object. It takes in a third parameter which is a response value. The lower it is the slower the response will be. Response affects the amount of time it takes to come back and mute.

Values between 1-20.

http://www.pdpatchrepo.info/hurleur/gate~.pd

Else you could try [moses], or maybe [clip] it depends on what you wanna do

bad gate go home
baaad