“Live in concert”
Sometimes I see a music video entitled like this, but it seems strange to me.
A concert should be always “live”.
There’s no concert which is not “live”.
So it seems to me a little wordy, like “headache in the head”.
(A headache should be always in the head, and you don't have to say "in the head".)
Could anybody explain this to me?
yes, you are correct the 'live' can be redundant, but does give an added angle from an advertising point of view.
Also, it signifies that the person, group or commedian will be there in person. Not, pre-recorded with only a video-wall broadcast or video link-ups.
Imagine (no pun intended) if there was to be a John Lennon 'concert'. Recordings & video footage could be shown, and all in attendance would have been to a concert (of sorts), but it could never be called 'live in concert'.