These tracks have all been purpose made by Timothy for the choirs and projects with whom he has been involved.
The key purpose for these tracks is to aid accessibility in choir training, taking the heat off the requirement to be able to read sheet music.
With this in mind, they are not created as a demonstration of excellent singing technique, not least as Timothy is a tenor (and only a tenor). He has sung all parts in these tracks in order to help singers learn the music.
It is down to the choir trainer to get the best sound out of their choirs.