The Edinburgh Jazz & Blues Festival launches its 2015 programme today, with a broad range of international and Scottish jazz, blues, soul and gospel talent. The full programme won't be released until Thu 30 Apr, but in the meantime there's more than enough to give a flavour of this year's lineup.

When the EJBF started out in 1978 it was, like most Scottish jazz festivals, strongly trad-flavoured, but over the years it's steadily broadened its horizons. This year, the festival's Cross the Tracks weekend at Summerhall will showcase the places where jazz, hip-hop and electronica get jiggy with each other; Hidden Orchestra is on the gig list. For Cross the Tracks, Chapel Perilous Sound System will install quadrophonic sound in the venue.

At the opposite end of the historical spectrum, the festival has been talent-scouting in the US for new blues talent, with drummer Cedric Burnside, Mississippi singer Mr Sipp, singer / harmonica player Brandon Santini and guitarist Ben Rice making appearances.

For those more inclined to straight-ahead jazz, there's Oakland-born, Blue Note-signed post-bop trumpeter Ambrose Akinmusire; Melissa Aldana, a Chilean tenor player with a dark tone and a smart, exploratory attitude, and the first female non-singing musician ever to win the Thelonious Monk Institute of Jazz's young musician award; and the welcome return of the Colin Steele Quintet.

Squarely within the Crowd-pleasing Headliners category are Jools Holland's Rhythm and Blues Orchestra; gypsy / swing combo Rose Room, and George Benson, who after decades of lucrative pop crooning has in recent years given some welcome reminders of what a phenomenal guitarist he is.

You can never have too much Duke Ellington, and the Scottish Jazz Expo features the Edinburgh Jazz Festival Orchestra exploring the Monster's post-WWII repertoire in a concert called Echoes of Ellington. The Expo also has performances from the great Brian Kellock, Kim Macari and Enrico Zanisi, and a collaboration between Richard Kass and Snarky Puppy's Cory Henry.

There's plenty of free music too: on 18 July, the Mardi Gras will turn the Grassmarket into a party (the Mardi Grass, if you will – yes, relax, we know that's not what 'gras' means) and on the following day, Princes Street Gardens is, as always, the venue for the festival's annual Carnival, with costumes, music and dance. The Edinburgh Napier Jazz Summer School will welcome young musicians to the craft of making the difficult look not just easy but graceful.

The Edinburgh Jazz & Blues Festival runs from Fri 17–Sun 26 Jul 2015.