During the course of music-history the expressivitiy of affects has changed by period. Until to the baroque era - so I would say - both the listener and the performer received their affects from the instrument. Later on the performer put inside the instrument his own affects and in this way he transported them to the listener.
Interestingly enough children upto the age of puberty are very receptive to early music and they consider it by all means as magical-fascinating. Later on with begin of puberty they notice the difficulty to express themselves by this music or rather they feel other directed. Of course they don't speak in this terms about that fact but they turn to the "Sensitive Style" which they consider to be totally awesome.
According to my viewpoint the charm of the affects in early music results in the fact that it refers to natural experiences accessible to everybody. It refers to an universe of common emotional worlds and prisms of experience. 450 years ago there weren't any exact (e.g. logically developed) theories of perception and spiritual conditions. The insights were heuristic and everybody had to find out and to adopt explanations on his own.
By this way a strong affective binding between the musician and the music was generated. His performance was spectacle and role play at the same moment. He didn't ask about the will and desire of the composer (in case he was actually known) but how he dealt with the affects inside the piece he played. He turned out to be in the situation as a role-player. The interaction with the spectators was done by affects transported through the instrument.