W. Stanley Vann (1910-2010) was an extrememly distinguished British organist and composer, most remembered for his tenure as Organist and Master of the Music at Peterborough Cathedral (1953-1977).
Rather than try to give a "squeezed-in" biography, I'll give this link to a website created by his son, which gives full details, recordings, lists of works, etc.
http://www.stanleyvannmusic.org.uk/index.htm (NO LONGER VALID)
Vann was a distinctive and distinguished composer, and his works have a "certain sound" to them. His old recordings, made with the choir of Peterborough, were an ENORMOUS influence on me. A former assistant from the pre-Peterborough days told me, "Stanley could get as much, if not more, from 'ordinary boys', as Willcocks (meaning the famous David Willconcks) could get from 'Kings-type boys', meaning of course King's College, Cambridge.
The "Pavan" was published in 1990 by Oecumuse. It bears the dedication "for Martyn and Anne". If this was a "wedding processional", it's a highly unusual one...
The piece is typical of Vann's writing, particularly in it's harmonic language. There are two "solos" the first played on the Solo Orchestral Oboe and the second on the Solo Clarinet - both as Vann directed.
There is a chordal middle section.
A "pavan" is often defined as a "slow processional dance" and this one COMPLETELY fits the definition. The rhythmic pattern that appears in the first measure appears in every measure, although the middle section uses the rhythm in a slightly different manner.