Since the concept of Piper to The Sovereign started with Angus MacKay in 1843, there have been 14 others consecutively; (this does not include "Honorary" pipers and assistant pipers etc.). The current, (2016) and 15th Sovereign’s Piper is Pipe Major Scott Methven of The Argyll and Sutherland Highlanders.
During my 10 years at Balmoral I played along with three Sovereign's Pipers; the late PM Brian MacRae (Gordon Highlanders), PM Gordon Webster (Scots Guards) and PM Jim Motherwell (Argyll and Sutherland Highlanders).
Our piping duties were mostly during the evenings, however on the occasional (rare) absence of The Sovereign's Piper I would also assume his piping duties at Balmoral Castle. These included playing outside the Castle in the mornings and being Master of Ceremonies at the Ghillie's Ball.
My uniform was virtually identical to the Pipe Major's, being of Balmoral tartan which may only be worn by The Royal Family and their pipers. However my silver accoutrements were slightly different, being newly commissioned in 1990 whereas the Pipe Major's were handed down, some from Victorian days. He also wore his badges of rank and two eagle's feathers rather than one.
We both carried HM The Queen's pipe banner around the dinner table and on formal occasions.
The Sovereign's Piper would travel with Her Majesty and play for her at Buckingham Palace, Windsor Castle, Holyrood Palace in Edinburgh, and at Balmoral in Aberdeen-shire. Personally employed pipers such as myself would normally only play in the vicinity of Balmoral.
Since leaving Royal Service I have been invited back regularly and have played along with the last four Sovereign's Pipers; PM Cuthbertson (Royal Scots), PM Potter (RSDG), PM Rodgers (Irish Guards) and PM Methven (A & SH).