Thanks a lot.As far as I understood, portato should be played by distinct arm motions , but not deliberately aiming at separating the notes.Is that right?[...]
I think you are wrong on both counts.
First : You certainly don't need "distinct arm motions" to play a
portato passage. Whether the passage is a simple four- or five-note portion of a scale passage or something longer, you certainly aren't going to move your arms to play such a passage
portato, just as you wouldn't, necessarily, if it were a
legato or a
staccato passage. In other words "distinct arm motions" don't produce
portato.
As the dictionary defines portato, it is "a musical articulation midway between
staccato and
legato. It is indicated by a slur over notes bearing a staccato dot or by a tenuto marking combined with a staccato dot." Often, in the case of Baroque music,
portato isn't even indicated - except, perhaps, in heavily edition editions - since portato is often considered standard performance practice in much of Baroque music, depending on the context.
Second : In effect, then, there
is a slight separation of notes when playing
portato, otherwise you are playing legato.
Regards,