I own both the mad hen and mad hen 2,  the mad hen is a little raspier and I know this sounds stupid but meaner more urgent sounding.  The mad hen 2 is less raspy,  a little cleaner sounding call.  I know the birds go nuts with the original.  Anxious to test the mad hen 2 this spring.  A lot of guys on here will attest to their success with the original.  Scoot