I enjoy enormously this recording of the violin music of Heinrich Ignaz Franz von Biber. It sounds like a whole ensemble, doesn’t it? The group is called Romanesca.
Biber is middle Baroque, when they were still having fun with their style. Most fun is a piece called Sonata Representativa where he tries to imitate sounds, somewhat reminiscent of Messiaen. Wait, that can’t be right. It must be the other way around. He’s doing a nightingale, a cuckoo and a quail, for instance. The nightingale somewhat resembles a cadenza that starts slowly. With the cuckoo he puts the call on an inner voice that you have to listen for, like a cantus firmus. The croak of a frog is done with sliding minor seconds. As is the crowing of the cock. Cats slide discordantly and musketeer’s march to bagpipes, of course. Lots of fun.
There is an extended piece for solo violin that builds on a four note minor repeating bass, one of the major building blocks of the middle Baroque, called a Passacaglia. They are edging toward tonality, Biber is much more tonal than Monteverdi, but the quicksand has not yet quite caught them, and they can experiment. Once tonality completely takes hold, you are tonal whether you want to be or not. Schoenberg invented a whole system to avoid the sense of the tonal magnet, and still it sounds tonal a lot of the time.
Middle Baroque is where it’s at.