I was going through some of my books looking for something unrelated and I noticed in the book The Dawn of Modern Warfare by Hans Delbruck I had a couple references to Robert Monro that I had bookmarked. On page 191 there's a short paragraph saying:
The English customarily shouted aloud while attacking, whereas the Scots moved silently against the enemy. The Scot Monro made fun of the imperial soldiers, who shouted "Sa, sa, sa" during the attack; he said they did this like the Turks, as if shouting would frighten brave soldiers. The Danes and Swedes, too, advanced in silence."
I always thought it sounded dramatic when we charged our pikes and made a staccato shout as the pikes dropped (Some of our pikemen used to turn it into a long yell which I found annoying -I always thought a short staccato shout sounded more impressive and disciplined.)
I probably used this quote at one time or another when I edited the newsletter way back when, but it suggests our noise may have been stretching things, although it's probably something that could be left to the discretion of the Captain since a single, audience pleasing, shout at the charge of the pikes followed by silence while advancing might be a reasonable compromise.