Cult Aussie minimalists The Necks remind us that the best experimental music is both simple and challenging

Throughout most of The Necks’ first set on the opening night of their four-day Cafe Oto residency, pianist Chris Abrahams hardly pecks at more than about five or six notes. Similarly, as their flexuous, droning river of sound unfurls, bassist Lloyd Swanton swan dives between two or three. Meanwhile, drummer Tony Buck strokes and swipes and scrapes his kit with the aid of some brushes and bells. On the surface, each player individually teases out the most rudimentary of figures. Fused together, however, they seem to create their own weather system; not only that, they conjure one of the most unnerving and demanding live experiences of the festival (probably). At times, the tension they create amid their throbbing, cinematic clamour is almost too much to bear. What keeps your eyes fixed on them though, is their ability to defy any expectation of what comes next, and that is the key to their enduring appeal. Jamie Skey

The tuba is made for dubstep and acid house

Sons Of Kemet's fusion of spiritual jazz, African and Caribbean music, and contemporary club rhythms is one of the freshest sounds in contemporary British music, and in the sweaty confines of Dalston's Rich Mix, the sax-tuba-drums quartet play a scorcher. Wearing a hooded silk robe, Shabaka Hutchings ramps up the energy with every tightly coiled phrase and insistent repetition on his tenor saxophone. Tom Skinner and Seb Rochford's twin drum approach is not so much a dialogue as an ecstatic communion, as drum circle polyrhythms and Barbadian marching band tattoos are whipped up into grooves as fluid and relentless as the hottest bass music. Theon Cross plays the tuba as if it's a Roland 303, generating deep, Flubber-like bass lines as well as wild squalls, percussive pops and dubstep bwaps. As energetic as the gig is, Sons of Kemet display masterful sense of dynamics and pace, building tension by pushing against the music's structures, without ever going completely off map. Stewart Smith

The biggest names don’t necessarily provide the biggest thrills

While not of the same standing as some of her mentors – Chick Corea, Ahmad Jamal, Stanley Clarke – Japanese fusioneer Hiromi is nonetheless a marquee jazzer in her own right. Much like soul-jazz bassist Esperanza Spalding and hip-hop enabler Robert Glasper, the 36-year-old Shizouka-born pianist has been drawing a younger, hipper, more rock-inclined audience towards this reportedly ailing genre since the release of her explosive debut, 2003's Another Mind.

Over the years, Hiromi has been known to stun and hypnotise audiences with her firework-bright fusion of Fats Waller-fuelled stride riffs, euro classical sophistication, prog-rock suites and latin rhythms. The problem is, nine albums down the road, and she’s barely altered her flashy script one bit.

Since sidelining team Sonicbloom (bassist Tony Grey, drummer Martin Valihora and guitarist Dave Fiuczynski) and subsequently hiring seasoned studio pros Anthony Jackson (bass) and Simon Phillips, the pianist has lost much of her spice and intimacy. And so it is tonight. Her winding, almost exhausting flash-bang formula is scaled up to almost arena-friendly proportions, while each composition briskly unfurls quite predictably: taut ostinatos spring into full-on prog-rock spirals which dissolve into swing breakdowns before launching into uplifting, lyrical choruses... ad infinitum. Jamie Skey

London-Chicago: The Windy City gets the smoke going

London-Chicago Vibration is a 50th anniversary tribute to the Chicago-based AACM, led by multi-percussionist Orphy Robinson and an all-star band of UK-based improvisers including legendary drummer Louis Moholo-Moholo, vibist Corey Mwamba and saxophonist Jason Yarde. The opening spoken word and percussion piece, performed to a short film, is overlong, but the show takes off once the full band takes the stage. Building upon a live beatbox loop, vocalist Cleveland Watkiss leads the ensemble into a powerful version of 'Strange Fruit'. Over a muscular John Edwards bass groove, Watkiss takes the melody around sharp corners, accentuating the song's anger and pain. Later in the set, accordionist Janez Dvoč weaves in a Parisian melody, in honour of those murdered in terror attacks the previous night. In tribute to the AACM, the ensemble improvises on a Wadada Leo Smith theme, before encoring with an appealingly ramshackle run through Art Ensemble Of Chicago's classic 'Theme De Yoyo'. Stewart Smith

Glasgow has an answer to American Grammy-winning jazz-funk collective Snarky Puppy

The shit-hot Snarky Puppy, who have given jazz a much needed shot of adrenalin to the arm, were one of the major talking points at the last two London Jazz Festivals. Not performing this year, it feels like there’s something of a Snarky Puppy-shaped hole in the bill. Never fear. Glasgow’s equally sprawling, party-starting fusion community Fat Suit stylishly plug the gap. Known for raising spirits in war-torn Ukraine, the band set the Southbank’s Clore Ballroom on fire with their riot of synth-drenched riffola and blazing brass anthemia. While their name seems quite dowdy, their tunes are anything but. Jamie Skey

Kamasi: Keytars needn't be a novelty

Kamasi Washington and the Next Step's sell-out show at the Barbican is a gloriously life affirming experience. Support act GoGo Penguin's drippy Coldplay-do-Nordic-minimalism is swiftly forgotten when the Los Angeles saxophonist and his seven piece band, augmented by his father Rickey Washington on flute and soprano sax, take the stage. Stripped of their choirs and strings, these tracks from The Epic positively soar with the soulful intensity of spiritual jazz and the swagger of hip-hop. When he isn't playing piano with the super-charged modalism of McCoy Tyner circa Enlightenment Brandon Coleman is strapping on a Moog keytar to unleash lurid streams of Bernie Worrell/George Duke flavoured cosmic slop. Miles Mosley's bowed wah-wah bass is almost as outrageous, channelling the vicious funk of Charlie Haden on Ornette's 'Rock The Clock'. Debussy's 'Claire De Lune' is transformed into a gorgeous jazz waltz, burnished with Washington's tenor and Ryan Porter's wonderfully expressive trombone, while 'Henrietta Our Hero' is a fine showcase for Patrice Quinn's classy vocals. From the extended solos to a ridiculous drum duel, there's a whole load of showmanship here, and why not? Washington takes it to the bridge and then out into the cosmos. Stewart Smith