Gallus, also known as Jacob Handl (among other names; the Groves entry reads: Handl [Gallus, Händl, Handelius], Jacobus [Jacob, Jakob]), is not so well-known these days. I first became familiar with his work in 1991 and really fell for it. That work, a Gaudent in coelis, has not been recorded, to the best of my knowledge. Not surprising considering that he's a not-so-well-known Slovenian composer who died over 400 years ago and wrote over 500 works.

This is all neither here nor there: I like his work and hope you will, too. The excerpt below is from the Gloria of his Missa super Sancta Maria.