Yes... and whatever the actual instrument used to play the soundtrack, Tom the Cabin Boy holds up a concertina and calls it such - as evidenced at 2:19 in episode "Monster Ahoy" at http://www.youtube.com/watch?v=kRMpSOkZcT8 . John Kirkpatrick did make the distinction but I guess I was remiss in not going into all the details in my intial post!