The audience’s appreciation for Keith Jarrett’s first solo concert in London since 2008 grew louder and more passionate as the evening developed tonight. By the end of the fourth and final encore, the utterly devoted London audience was on its feet, whistling, cheering, saluting its hero.

Reports from the weekend’s Dublin concert had hinted at Keith Jarrett’s current mood: “the bonus we got was all the between-piece patter that he did…he was very funny” wrote Ronan Guilfoyle. And that was exactly what transpired. An example from tonight: “Does anybody have a chord they’d like to request?”

I don’t know the Dublin audience, but the London Jarrett audience surely wears its adoration for him more obviously on its sleeve than most. And so you have to wonder if Jarrett – (apart from giving the users of phone cameras the earfuls of abuse they deserved, and probably wanted) – doesn’t treat us here to a little more mischief, a little more paradox, a little more playfulness.

The first set had started in the knotty gnarled angry discordant piano world of, say Boulez’s 2nd Sonata or Ligeti’s Chromatic Fantasy. Some piano cognoscenti told me they loved all that unforgiving complexity, but I wondered if it wasn’t just a device to remind the listener that beauty and shape can more readily assert their value and appeal if they are seen to emerge from formlessness and chaos. If I am right, then the bucolic innocence of the second number did seem to score that debating point rather well, before stiffening its sinews to become a dark and insistent pasodoble, with Jarrett the matador stamping his outsize shoes.

The sheer variety of mood, the things tried and moved on from, the influences summoned from thin air were what stay in the mind. The first improvisation of the second half seemed to start in Debussy territory, become more modal and Messiaen-ish, then searching and fantasizing, to land in a final lyrical moment of sheer beauty. All you knew by the end of that particular journey was that you had travelled a long way from where you’d started.

What were those encores? No 2 was Cole Porters Miss Otis Regrets. No 3 was a blues. Anyone?

Another moment which left plenty to think about was a gospelly South African vamp which got abandoned after less than a minute. A teaser, an unfinished sketch, a fragment which will doubtless find its completion one day, in another concert hall in another time zone. Jarrett was playing with the conventional form of the concert, happy to leave an audience thinking what might have been. And why not?

Jarrett gave his legions of admirers exactly what they wanted tonight, and will definitely have made some new converts too.