Board Thread:Roleplay/@comment-24965182-20160107095600/@comment-26142892-20160108220739

Urahara: There's usually a balance between you and your zanpakutou. If you put out a lot of spiritual pressure that your zanpakutou can't handle, you won't be able to hear it. The other end is if you can't handle your own spiritual pressure, you'll be weakening yourself.