We have no more than a vague image of it: the quality of the singers in Bach's time. We do know the subdivision used by the Thomascantor based on what they performed. That those performances in the highest category must have been of considerable quality is evident from the motets BWV 225-230 composed by Bach alone. What we also know is that the choir members who qualified for this also had to fulfill a solo role. The surviving choir parts show this unequivocally.
In Bach's Roots we hear that reflected: from the twelve-voice choir Voces Suaves, a number are also heard in a solo role, which brings me to the main criticism of this recording. For what stands out in particular is the contrast between the particularly beautiful-sounding vocal collective and the less striking and sometimes less precise solo contribution to it (as in Georg Christoph Strattner's Die Welt, das ungestüme Meer). But also as if more has been invested in the notes than in the interpretation of them, which somewhat detracts from the spontaneous character of these performances. The Akademie für Alte Musik Berlin ('Akamus') is, as it usually is, a reliable partner, though I often wondered whether it would not have been better to have this project conducted not by the concertmaster, but by a separate conductor with more control over this certainly not simple matter.