“About 1990, I found it among lots of old junk under the stairs I told my dad and he told me to keep it. I’ve played it since and enjoyed it, but I have lots of guitars, including lots of my dad’s, so I thought that a collector might value it a lot more than I do and get more enjoyment from it.”I never got the chance to ask Hendrix why he set it on fire – I wasn’t born – but I’m sure it was intended to be an amusing spectacle. Whatever the reason, it’s a part of rock’n'roll history.”The guitar is being handled by Cooper Owen’s, the music memorabilia auction house that once sold John Lennon’s piano for £1.5m.The guitar was first auctioned, without fanfare, in Las Vegas several months ago, where the bidding reached $500,000. Dweezil withdrew it from sale after hearing from Ted Owen, one of the London auction house founders, who said it would fetch more in the UK.Hendrix, recently voted the world’s best guitarist, died aged 27 in 1970, and Zappa succumbed to cancer in 1993 aged 52.. Youth orchestras – and this time it was the turn of Claudio Abbado’s Gustav Mahler Jugendorchester – come in greater numbers than their grown-up counterparts.

The idea that they are growing into their sound is a nice one to hold on to. What you see – many doublings and a string section bigger than any even their namesake conceived – is not necessarily what you hear. The most striking feature of Abbado’s orchestra is its lightness and transparency. If the piece is, as some claim, a conscious reinvention of the Baroque concerto grosso, then the emphasis of this performance was on the “grosso” You couldn’t see for strings. The percussion, relegated to one corner behind a bank of double basses, felt remote.

No longer the solo group, no longer the driving force, the horse-power under the bonnet.What I missed here – particularly, of course, in the two allegro movements – was a tight, wiry, quick-reflex sound. Even where these youngsters were fizzing with energy, the sheer weight of their numbers, the blizzard of tremolando effects, dissipated the effect The performance was altogether bigger on atmosphere. The sound of many hushed voices at the outset – a furtive fugue if ever there was one, a fugue that almost dare not speak its name – was eerily disembodied like a remnant of past performances heard in this hall. Spooky, too, were the slow movement’s slippery glissando effects. Very Stanley Kubrick.Martha Argerich, the evening’s soloist, has now turned up for three consecutive Prom seasons, which must be some kind of record for a lady whose reputation for cancellation must be up there with the late Michelangeli. But you can see that she’s in her element here, doubly so when surrounded by young musicians and backed up by her friend Claudio Abbado with whom the rapport is telepathic. Their performance of Ravel’s G major Piano Concerto was initially so relaxed, so casual, so effortless as to be almost horizontal.But never be deceived by Argerich.

What was truly remarkable about this reading and this playing was its illusory nature. The essence of the piece is jazz, and jazz is about furthering the threshold of improvisation and still coming home. Argerich probably plays this piece as much if not more than any other concerto in the repertoire and yet not one phrase could safely be predicted. Which is not to say that she strove to be unpredictable, just that she was unpredictable. A shift of emphasis here, a slightly different slant on a phrase there, a rhythm suddenly spiked to catch you unawares. She didn’t wait for quiet from the audience before beginning her soft, museful vamp into the slow movement We could listen if we liked.