This Is the position on the polyphase filters, that happen to be all-pass filters and only modify the stage. The period relationship amongst The 2 polyphase filters in this instance is these kinds of that it will compensate for that extra "twist" so which the stage in between the desired https://share.evernote.com/note/91c6354d-2887-12d0-6d41-1b26614dcfdf