Joni sings most affectingly to her friends: Betsy, Sharon, Carol. Her observations have the musing, informal tone of letters and conversation, studded with the surprising details which have always lent her songs their special, precise resonance, such as the recent reflection on her friends' children: "We look like our mothers did now/When we were those kids' age".
She has an electric guitar now (a fat-bodied single-cutaway jazz model, to which she has adapted her folky finger style with typical originality) and a Hollywood-slick four-piece backing band. Still, though, the prevailing thrust is of an honesty which consistently pierces and brings down romance on the wing: she wants to be a wild thing, running fast and free, but she is increasingly willing to admit without self-pity to the banal frailties which to some extent hobble every life, be it ever so grand.
Saturday evening's concert followed the path of her most recent album by revelling in the injection or rock 'n' roll beneath the complicated surfaces of her song structures: her guitarist, Michael Landau, provided raging post-Hendrix power chords and solos in "You Dream Flat Tires" and "Wild Things Run Fast". Russell Ferrante (keyboards), Larry Klein (bass guitar) and Vince Colaiuta (drums) sewed up a variety of glistening backdrops, taking their cue from her trademark swaying strum and allowing her voice to range freely through its wonderful variety of timbre.
Towards the interval, she shuffled the deck. "God Must Be a Boogie Man", from the unsuccessful Mingus album, swung on finger-snapping bass and wire brushes on the snare drum; the early "He Played Real Good For Free", still a moving song, was accompanied only by her own piano; "Big Yellow Taxi", in which she rather endearingly muddled up the words, was done folk-club style, alone with her guitar; and she sat at the dulcimer for "A Case of You".
The big set pieces, one in each half, were taken from the underrated Hejira; first "Song to Sharon", in which her sustained intensity took the whole concert up a gear or two; later "Refuge of the Roads", autobiography in the picaresque and metaphysical modes. Her recasting of Leiber and Stoller's "(You're So Square) Baby I Don't Care" lightened the mood; the marvellous "Chinese Café", which so brilliantly interpolates snatches of "Unchained Melody", brought us back to hushed introspection with the kind of emotional combination-punch she devises better than anyone.