SPACE & TIME - TECH NOTES:
All the above processes are employed in a very similar way to how they are used in a live sound mixing context, when they are used to balance the sound to suit the characteristics of the live concert venue, as well as for aesthetic reasons. No other studio techniques have been used, and no sounds at all have been added (oh yes, except for someone going "sshhh!", but you're very unlikely to spot that).
On virtually all commercially released 'live' albums the original recordings
are 'sweetened'. That is to say, vocals and out-of-tune notes on the
instruments are very often re-recorded later in the studio - and on
some occasions ALL of it is re-recorded and only the ambience of the
live show is retained! Also very often extra vocals or sounds are carefully
blended in to fill out the sound. No mention is usually made of this,
but trust me, this is totally the norm for live albums.