The important and highly respected William Boyce (1711-1779) was a significant composer and musician of his time. His works and contributions still stand tall today.
Rather than give the same biographical information in each of these uploads, I thought it perhaps more "interesting" to share a few thoughts that I had about the music, and how I got the sounds that you are hearing.
I think that the Hereford Willis is actually an excellent instrument for 18th century music, and the sounds are all there - you just have to be slightly creative to make it all work, and do so WITHOUT pushing buttons, which would not have been possible in the composer's time.
This voluntary is a "Cornet Voluntary," and I'm going to "call" the "prelude" in this voluntary "saraband-like." If I'm incorrect in the use of that term, please correct me. As always, the "prelude" is played upon the Diapasons. When the score says "Diapasons" the term would mean the 8' Open Diapason/s and the 8' Stopped Diapason as well. It might include a light 4' as well.
The Cornet that you are hearing is actually the Choir Cornet coupled to the Great Flutes 8' & 4'. The Choir alone is a bit too "thin".
The "bass" is played upon the Swell Diapasons, and the "Echo Cornet" is the Flutes 8' & 2' from the Solo organ. While I think this is highly effective, it probably is not quite the "academically correct" echo.
The written ornamentation is extremely "busy" and is very elaborately written with it's rapidly repeating "mordents."
You really need to look at the score which is attached below, as well as a photo of a portrait of William Boyce.
I never really "played" these pieces. A few of them I used as "prelude/postlude music," but it surprises me to find them as challenging as I am! They require a clean and "polished" touch, and would make great learning pieces, that are highly suitable for recitals or church use.